Home Embedding of Supplementary Results in Strong EMT Valuations and Strength
Article Open Access

Embedding of Supplementary Results in Strong EMT Valuations and Strength

  • Salma Kanwal EMAIL logo , Mariam Imtiaz , Zurdat Iftikhar , Rehana Ashraf , Misbah Arshad , Rida Irfan and Tahira Sumbal
Published/Copyright: May 30, 2019

Abstract

A graph is said to be edge-magic total (EMT if there is a bijection Υ : V() ∪ E() → {1, 2, …, |V() ∪ E()|} s.t., Υ(υ) + Υ(υν) + Υ(ν) is a constant for every edge υνE(). An EMT graph will be called strong edge-magic total (SEMT) if Υ(V()) = {1, 2, …, |V()|}. The SEMT strength, sm(), of a graph is the minimum of all magic constants a(Υ), where the minimum runs over all the SEMT valuations of , this minimum is defined only if the graph has at least one such SEMT valuation. Furthermore, the SEMT deficiency of a graph , μs(), is either the minimum non-negative integer n such that nK1 is SEMT or +∞ if there will be no such integer n. In this paper, we will present the strong edge-magicness and deficiency of disjoint union of 2-sided generalized comb with bistar, path and caterpillar, moreover we will evaluate the SEMT strength for 2-sided generalized comb.

MSC 2010: 05C15

1 Basic Terminologies and Preliminary Results

Let = (V, E) be a simple, finite, planar and undirected graph having p = |V()| and q = |E()|. The labeling of a graph is a map that carries graph elements (vertices p, edges q or both) to numbers (usually positive integers). If the domain of the given graph is the vertex(edge)-set then the labeling is described as a vertex(edge) labeling. But if domain be the both vertex and edge sets, that labeling will be the total labeling. Other domains are possible.

An EMT labeling of a graph is a one-to-one mapping Υ from V() ∪ E() onto the set of integers {1, 2, …, p + q} with the property that, there is an integral constant “a” such that Υ(υ) + Υ(υν) + Υ(ν) = a, for any υνE(). If Υ(V()) = {1, 2, …, p} then an EMT labeling is called SEMT labeling. A graph is called EMT(respectively, SEMT) if ∃ an EMT(respectively, SEMT) labeling of . The concept of EMT labeling was first given by Kotzig and Rosa [1, 2], using a different name “magic-valuations”. Interest in these labelings has been lately rekindled by the paper on this subject due to Ringle and Lladó [3]. Shortly after this, Enomoto et al. [4] defined a more restrictive form of EMT labeling, namely SEMT labeling (which Wallis [5] refers to as Strong EMT labeling) and conjectured that every tree is SEMT. Many researchers have considered SEMT labeling for trees to verify this conjecture. Lee and Shah [6] proved this conjecture for trees with upto 17 vertices by the help of a computer. Javed et al. [7] provided the SEMT labeling for the 2-sided generalized comb. In [4] Enomoto et al. showed that all caterpillars possess SEMT labeling. The combined effort of Figueroa-Centeno, Ichishima and Muntaner-Batle [8] provide a necessary and sufficient condition for a graph to be SEMT i.e.,

Lemma 1

[8] A (p, q)-graph is SEMT if and only if there exists a bijective function Υ : V() → {1, 2, …, p} such that the set

S={Υ(υ)+Υ(ν):υνE()}

consists of q consecutive integers. In such a case, extends to a SEMT labeling of with the magic constant a = p + q + min(S), where

S={a(p+q),a(p+q)+1,,a(p+1)}.

To understand the lemma 1, we consider an example, see fig. 1, where it is shown that if a graph constitutes consecutive edge-sums then its super edge-magicness is assured.

Figure 1 
(i) A Bistar BS(5, 4) with consecutive edge-sums, (ii) A SEMT Bistar BS(5, 4) with magic constant c = 28
Figure 1

(i) A Bistar BS(5, 4) with consecutive edge-sums, (ii) A SEMT Bistar BS(5, 4) with magic constant c = 28

To prove the results in this paper, we will frequently use this Lemma. Conditions given in Lemma 1 will be easier to work with than the original definition.

The (super) EMT strength of a graph , denoted by (sm()) m(), is defined as the minimum of all magic constants a(Υ) where the minimum is taken over all the (super) EMT labelings of . This minimum is defined only if the graph has at least one such (super) EMT labeling. One can easily perceive that, because the labels are from the set {1, 2, …, p + q},

p+q+3sm()3p.

Avadayappan et al. first introduced the notions of EMT strength [9] and SEM strength [10] and found EMT strength for path, cycle etc, also the exact values of SEMT strength for some graphs. In [11, 12, 13] the SEMT strengths of fire crackers, banana trees, unicyclic graphs, paths, star, bistar, y-tree and the generalized Petersen graph have been observed.

Kotzig and Rosa [1] verified that for any graph there exists an EMT graph χ s.t. χnK1 for some non-negative integer n. This fact leads to the concept of EMT deficiency of a graph , μ(), which is the minimum non-negative integer n s.t. ∪ nK1 is EMT. In particular,

μ()=min{n0:nK1isEMT.}

In the same paper, Kotzig and Rosa gave the upper bound for the EMT deficiency of a graph with n vertices i.e.,

μ()Fn+22nn(n1)2

where Fn is the nth Fibonacci number. Figueroa-Centeno, Ichishima and Muntaner-Batle [14] defined a similar concept for SEMT labeling i.e., the SEMT deficiency of a graph denoted by μs() is the minimum non-negative integer n s.t. nK1 has a SEMT labeling, or +∞ if there is no such n, more precisely,

If M() = {n ≥ 0 : nK1 is a SEMT graph}, then

μs()=minM()ifM()ϕ+ifM()=ϕ

It can be easily seen that for every graph , μ() ≤ μs(). In [14, 15], Figueroa-Centeno et al. provided the exact values of SEMT deficiencies of several classes of graphs. They also proved that all forests have finite deficiencies. Ngurah et al. [16], Baig et al. [17] and Javed et al. [18] gave some upper bounds for the SEMT deficiency of various forests. In [19], Figueroa-Centeno et al. conjectured that every forest with two components has SEMT deficiency ≤ 1. In [20, 21, 22, 23], readers can find some related results. The examination of deficiencies in this paper will put evidence on this conjecture. However, this conjecture is still open too. One can go for [24] to review the work that has been done up till now on different types of graph labelings.

In the succeeding section, we will formulate the SEMT labeling and deficiency for forests formed by 2-sided generalized comb, bistar, caterpillar and path, with restricted parameters. For all graph-theoretic terminologies and notions, we refer the reader to [25, 26].

2 Main Results

Two-sided generalized comb denoted by Cbν,υ2 is defined in [7] and have proved that it admits SEMT labeling.

Definition 1

A 2-sided generalized comb, Cbν,υ2 , deduced from ν paths xı,1, xı,2, …, xı,ν ; 1 ≤ ıυ, ν ≥ 2 of length υ, where υ ≥ 3 is odd, by adding one new vertex xυ+12,0 and ν new edges xυ+12,ıxυ+12,ı+1;0ıν1, see Figure 2.

V(Cbν,υ2)={xı,ȷ:1ıυ,1ȷν}{xυ+12,0}
E(Cbν,υ2)={xυ+12,ȷxυ+12,ȷ+1:0ȷν1}{xı,ȷxı+1,ȷ:1ıυ1,1ȷν}
Figure 2 
2-sided Generalized Comb 
Cb4,52
$\begin{array}{}
\displaystyle
Cb^{2}_{4,5}
\end{array}$
Figure 2

2-sided Generalized Comb Cb4,52

Avadayappan et al. made a following remark about SEMT graphs i.e.,

Note 2. [10] Let Υ be a SEMT labeling of with the magic sum a(Υ). Then adding all the magic sums obtained at each edge, we get

qa(Υ)=νV()deg(ν)Υ(ν)+eE()Υ(e),q=|E()| (1)

This condition holds also for EMT labelings. The term deg(ν) in above expression is the degree of vertex ν which can be defined as the set of vertices adjacent to νV(), denoted by N(ν), and deg(ν) = |N(ν)| is the degree of ν in

There may exist a variety of SEMT labeling schemes for a single graph- if any graph admits a SEMT labeling then another distinct SEMT labeling will surely exist for the same graph because of the dual super labeling detailed in [27]- and of course there will be as many different magic constants as the distinct labeling schemes. Many researchers have found the lower and upper bounds of magic constants for various graphs. In this paper, we will find the bounds for the magic constants of 2-sided generalized comb.

Clearly, Cbν,υ2 ; ν ≥ 2, υ be an odd number ≥ 3, has νυ + 1 vertices and νυ edges. Among these vertices, ν – 1 vertices have degree 4, one vertex has degree 3, νυ – 3ν vertices have degree 2 and the remaining 2ν + 1 vertices have degree 1, see fig 2. Suppose Cbν,υ2 has an EMT labeling with magic constant “a”, then qa where q = νυ, can not be smaller than the sum obtained by assigning the smallest ν – 1 labels to the vertices of degree 4, one next smallest label to the vertex of degree 3, the q – 3ν next smallest labels to the vertices of degree 2, and 2ν + 1 next smallest labels to the vertices of degree 1; in other words:

qa4ı=1ν1ı+3ν+2ı=ν+1q2νı+ı=q2ν+1q+1ı+ı=q+22q+1ı=4ν(ν1)+6ν+2(qν+1)(q3ν)+(2q2ν+2)(2ν+1)+3q(q+1)2=5q2+6ν24qν+7q2ν+22

An upper bound for qa can be achieved by giving the largest ν – 1 labels to the vertices of degree 4, one next largest label to the vertex of degree 3, the q – 3ν next largest labels to the vertices of degree 2, and 2ν + 1 next largest labels to the vertices of degree 1, in other words:

qa4ı=2qν+32q+1ı+3(2qν+2)+2ı=q+2ν+22qν+1ı+ı=q+1q+2ν+1ı+ı=1qı=4(4qν+4)(ν1)+6(2qν+2)+2(3q+ν+3)(q3ν)2+(2q+2ν+2)(2ν+1)+q(q+1)2=7q26ν2+4qν+5q+2ν22

Thus, we have the following result,

Lemma 2

If Cbν,υ2 ; ν ≥ 2, υ be an odd number ≥ 3, is an EMT graph, then magic constant “a” is in the following interval:

12q(5q2+6ν24qν+7q2ν+2)a12q(7q26ν2+4qν+5q+2ν2);q=νυ

By a similar argument, it is easy to verify that the following lemma holds, because in SEMT, vertices receive the smallest labels.

Lemma 3

If Cbν,υ2 ; ν ≥ 2, υ be an odd number ≥ 3, is a SEMT graph, then magic constant “a” is in the following interval:

12q(5q2+6ν24qν+7q2ν+2)a12q(5q26ν2+4qν+7q+2ν2);q=νυ

2.1 Semt Strength of 2-Sided Generalized Comb

From SEMT labeling for 2-sided generalized comb formulated in [7], we have the magic constant:

a=2νυ+νυ2+4;υ121(mod2)2νυ+νυ2+4;υ120(mod2)

and by given lower bound of magic constants in Lemma 3, we have a(Υ)5q2+6ν24qν+7q2ν+22q, where q = νυ, thus we can conclude;

Theorem 1

The SEMT strength for 2-sided generalized comb Cbν,υ2 ; ν ≥ 2, υ be an odd number ≥ 3 is, for q = νυ:

5q2+6ν24qν+7q2ν+22qsm(Cbν,υ2)2q+q2+4,υ121(mod2)5q2+6ν24qν+7q2ν+22qsm(Cbν,υ2)2q+q2+4,υ120(mod2).

2.2 Semt Labeling and Deficiency of Forests Formed by 2-Sided Generalized Comb, Bistar and Caterpillar

Definition 2

Star on n vertices is denoted by K1,n–1, is given by the following set of vertices and edges:

V(K1,n1)={νı;1ın}
E(K1,n1)={ν1νı;2ın}

Bistar BS(ζ, ξ) is an acyclic graph on n vertices obtained from two stars K1,ζ and K1,ξ by joining their central vertices by an edge, where ζ, ξ ≥ 1 and ζ + ξ = n – 2,

V(BS(ζ,ξ))={zt:=1,2;0tΛ},

where

Λ=ζ;=1ξ;=2
E(BS(ζ,ξ)={z10z1t;1tζ}{z10z20}{z20z2t;1tξ}

Definition 3

[25] A caterpillar is a graph derived from a path by hanging any number of leaves from the vertices of the path. The caterpillar can be seen as a sequence of stars S1S2 ∪ … ∪ Sm, where each Sı is a star with central vertex cı and ηı leaves for ı = 1, 2, …, m and the leaves of Sı include cı–1 and cı+1, for ı = 2, 3, …, m–1. We denoted the caterpillar as Sη1,η2,…,ηm, where the vertex and edge sets are as respectively, V(Sη1,η2,…,ηm) = {cı : 1 ≤ ım} ∪ ı=2m1{υıȷ:2ȷηı1}{υ1ȷ:1ȷη11}{υmȷ:2ȷηm}, E(Sη1,η2,…,ηm) = {cıcı+1 : 1 ≤ ım – 1} ∪ ı=2m1{cıυıȷ:2ȷηı1}{c1υ1ȷ:1ȷη11}{cmυmȷ:2ȷηm}and|V(Sη1,η2,,ηm)|=ı=1mηım+2,|E(Sη1,η2,,ηm)|=ı=1mηım+1.

Theorem 2

For ν ≥ 2, υ = 2ε + 1, ε = 1, 2, 3, …

  1. Cbν,υ2 BS(ζ, ξ) is SEMT.

  2. μs( Cbν,υ2 BS(ζ, ξ – 1)) ≤ 1.

    where ζ ≥ 0 and

    ξ=1+υ(ν21)+1υ14+2υ24;ν0(mod2)2+υ(ν32)+3υ14+2υ24;ν1(mod2)

Proof

  1. Consider the graph Cbν,υ2 BS(ζ, ξ)

    Let p = |V()| and q = |E()|, then we get

    p=νυ+ζ+ξ+3q=νυ+ζ+ξ+1

    we define a labeling Υ : V( Cbν,υ2 ) → {1, 2, …, νυ + 1} as

    Υ(xυ+12,0)=νυ+ζ+ξ+3

    and consider the labeling Ψ : V() → {1, 2, …, p}.

    For υ12 odd;

    Υ(xı,ȷ)=ı2+υ(ȷ1)2;ı0(mod2),ȷ1(mod2)υȷ2ı12;ı1(mod2),ȷ0(mod2)
    Ψ(zt)=νυ2+t;=1,1tζνυ2+ζ+1;=2,t=0

    Let A = νυ2 + ζ + 1, then

    Υ(xı,ȷ)=A+ı+12+υ(ȷ1)2;ı,ȷ1(mod2)A+υȷ2ı2+1;ı,ȷ0(mod2)
    Figure 3 
SEMT forest 
Cb4,92
$\begin{array}{}
\displaystyle
Cb^{2}_{4,9}
\end{array}$ ∪ BS(5, 14)
    Figure 3

    SEMT forest Cb4,92 BS(5, 14)

    Ψ(zt)=νυ+ζ+2;=1,t=0νυ+ζ+2+t;=2,1tξ

    so,

    Υ(xυ+12,0)=Ψ(xυ+12,0)

    and

    Υ(xı,ȷ)=Ψ(xı,ȷ);1ıυ,1ȷν

    The edge-sums generated by the above labeling ”Ψ” are the set of consecutive positive integers S = {ħ + 1, ħ + 2, …, ħ + q}, where ħ = νυ2 + ζ + 2. Thus by Lemma 1, ”Ψ” can be extended to a SEMT labeling of and we obtain the magic constant a = p + q + ħ + 1, where ħ + 1 = min(S).

    For υ12 even;

    Υ(xı,ȷ)=ı+12+υ(ȷ1)2;ı,ȷ1(mod2)υȷ2ı2+1;ı,ȷ0(mod2)
    Ψ(zt)=νυ2+t;=1,1tζνυ2+ζ+1;=2,t=0

    Let A′ = νυ2 + ζ + 1, then

    Υ(xı,ȷ)=A+υ(ȷ1)2+ı2;ı0(mod2),ȷ1(mod2)A+υȷ2ı12;ı1(mod2),ȷ0(mod2)
    Ψ(zt)=νυ+ζ+2;=1,t=0νυ+ζ+2+t;=2,1tξ

    so,

    Υ(xυ+12,0)=Ψ(xυ+12,0)

    and

    Υ(xı,ȷ)=Ψ(xı,ȷ);1ıυ,1ȷν

    The edge-sums generated by the above labeling ”Ψ” are the set of consecutive positive integers S = {ħ′ + 1, ħ′ + 2, …, ħ′ + q}, where ħ′ = νυ2 + ζ + 2. Thus by Lemma 1, ”Ψ” can be extended to a SEMT labeling of and we obtain the magic constant a = p + q + ħ′ + 1, where ħ′ + 1 = min(S).

  2. Let ℧ ≅ Cbν,υ2 BS(ζ, ξ – 1) ∪ K1

    Here

    V()=V(Cbν,υ2)V(BS(ζ,ξ1)){z}

    and

    V(BS(ζ,ξ1)={zt:=1,2;0tΛ},

    where

    Λ=ζ;=1ξ1;=2
    E(BS(ζ,ξ1))={z10z1t;1tζ}{z10z20}{z20z2t;1tξ1}

    Let p′ = |V(℧)| and q′ = |E(℧)|, so we get

    p=νυ+ζ+ξ+3q=νυ+ζ+ξ

    Before formulating the labeling Ψ′ : V(℧) → {1, 2, …, p′}, keep in view the labeling Υ defined in (a). We define the labeling Ψ′ as follows:

    For υ12 odd;

    Υ(xı,ȷ)=Ψ(xı,ȷ)=Ψ(xı,ȷ);1ıυ,1ȷν

    with A = Ψ(z20) = Ψ′(z20)

    Ψ(z1t)=Ψ(z1t),0tζΨ(z2t)=Ψ(z2t),0tξ1Ψ(z)=νυ+ζ+ξ+2Ψ(xυ+12,0)=Ψ(xυ+12,0)=Υ(xυ+12,0)

    The edge-sums generated by the above labeling ”Ψ′” are the set of consecutive positive integers S = {ħ + 1, ħ + 2, …, ħ + q′}, where ħ = νυ2 + ζ + 2. Thus by Lemma 1, ”Ψ′” can be extended to a SEMT labeling of ℧ and we obtain the magic constant a = p′ + q′ + ħ + 1, where ħ + 1 = min(S).

    For υ12 even;

    Υ(xı,ȷ)=Ψ(xı,ȷ)=Ψ(xı,ȷ);1ıυ,1ȷν

    with A′ = Ψ(z20) = Ψ′(z20)

    Ψ(z1t)=Ψ(z1t);0tζΨ(z2t)=Ψ(z2t);0tξ1Ψ(z)=νυ+ζ+ξ+2Ψ(xυ+12,0)=Ψ(xυ+12,0)=Υ(xυ+12,0)

    The edge-sums generated by the above labeling ”Ψ′” are the set of consecutive positive integers S = {ħ′ + 1, ħ′ + 2, …, ħ′ + q′}, where ħ′ = νυ2 + ζ + 2. Thus by Lemma 1, ”Ψ′” can be extended to a SEMT labeling of ℧ and we obtain the magic constant a = p′ + q′ + ħ′ + 1, where ħ′ + 1 = min(S).□

All the remaining results of this paper will use the same labeling Υ as defined in the part (a) of Theorem 2.

Theorem 3

For ν ≥ 2, υ = 2ε + 1, ε = 1, 2, 3, …

  1. Cbν,υ2 Sζ,ξ,η is SEMT.

  2. μs( Cbν,υ2 Sζ,ξ–1,η) ≤ 1; (ν, υ) ≠ (2, 3)

    where ζ, η ≥ 2 and

    ξ=2+υ(ν21)+1υ14+2υ24;ν0(mod2)3+υ(ν32)+3υ14+2υ24;ν1(mod2)

Proof

  1. Consider the graph Cbν,υ2 Sζ,ξ,η, where

    V(Sζ,ξ,η)={cı:1ı3}{xı;1ıζ1}{yı;2ıξ1}{zı;2ıη}

    and

    E(Sζ,ξ,η)={cıcı+1:1ı2}{c1xı;1ıζ1}{c2yı;2ıξ1}{c3zı;2ıη}

    Let p = |V()| and q = |E()|, so we get

    p=νυ+ζ+ξ+ηq=νυ+ζ+ξ+η2

    Before formulating the labeling Ψ : V() → {1, 2, …, p}, keep in view the labeling Υ defined in Theorem 2.

    For υ12 odd;

    Take the previously mentioned labeling Υ (for υ12 odd) with A = νυ2 + ζ + η – 1. We define the labeling Ψ as follows:

    Ψ(xı)=νυ2+ı;1ıζ1Ψ(c2)=νυ2+ζΨ(zı)=νυ2+ζ+ı;1ıη1Ψ(c1)=νυ+ζ+ηΨ(yı)=νυ+ζ+η+ı;1ıξ2Ψ(c3)=νυ+ζ+ξ+η1Ψ(xυ+12,0)=νυ+ζ+ξ+η

    Ψ(xı,ȷ) = Υ(xı,ȷ) ; 1 ≤ ıυ, 1 ≤ ȷν

    The edge-sums generated by the above labeling ”Ψ” are the set of consecutive positive integers S = {ħ + 1, ħ + 2, …, ħ + q}, where ħ = νυ2 + ζ + η. Thus by Lemma 1, ”Ψ” can be extended to a SEMT labeling of and we obtain the magic constant a = p + q + ħ + 1, where ħ + 1 = min(S).

    For υ12 even;

    Take the previously mentioned labeling Υ (for υ12 odd) with A′ = νυ2 + ζ + η – 1. We define the labeling Ψ as follows:

    Ψ(xı)=νυ2+ı;1ıζ1Ψ(c2)=νυ2+ζΨ(zı)=νυ2+ζ+ı;1ıη1
    Figure 4 
SEMT forest 
Cb5,92
$\begin{array}{c}
\displaystyle
Cb^{2}_{5,9}
\end{array}$ ∪ S6,19,11 ∪ K1
    Figure 4

    SEMT forest Cb5,92 S6,19,11K1

    Ψ(c1)=νυ+ζ+ηΨ(yı)=νυ+ζ+η+ı;1ıξ2Ψ(c3)=νυ+ζ+ξ+η1Ψ(xυ+12,0)=νυ+ζ+ξ+η

    Ψ(xı,ȷ) = Υ(xı,ȷ) ; 1 ≤ ıυ, 1 ≤ ȷν

    The edge-sums generated by the above labeling ”Ψ” are the set of consecutive positive integers S = {ħ′ + 1, ħ′ + 2, …, ħ′ + q}, where ħ′ = νυ2 + ζ + η. Thus by Lemma 1, ”Ψ” can be extended to a SEMT labeling of and we obtain the magic constant a = p + q + ħ′ + 1, where ħ′ + 1 = min(S).

  2. Let ℧ ≅ Cbν,υ2 Sζ,ξ–1,ηK1, where

    V()=V(Cbν,υ2)V(Sζ,ξ1,η){d}V(Sζ,ξ1,η)={cı:1ı3}{xı;1ıζ1}{yı;2ıξ2}{zı;2ıη}

    and

    E(Sζ,ξ1,η)={cıcı+1:1ı2}{c1xı;1ıζ1}{c2yı;2ıξ2}{c3zı;2ıη}

    Let p′ = |V(℧)| and q′ = |E(℧)|, so we get

    p=νυ+ζ+ξ+ηq=νυ+ζ+ξ+η3

    Before formulating the labeling Ψ′ : V(℧) → {1, 2, …, p′}, keep in view the labeling Υ defined in Theorem 2.

    For υ12 odd;

    Υ(xı,ȷ)=Ψ(xı,ȷ)=Ψ(xı,ȷ);1ıυ,1ȷν

    with A = νυ2 + ζ + η – 1

    Ψ(xı)=Ψ(xı);1ıζ1Ψ(c2)=Ψ(c2)Ψ(zı)=Ψ(zı);1ıη1Ψ(c1)=Ψ(c1)Ψ(yı)=νυ+ζ+η+ı;1ıξ3Ψ(c3)=νυ+ζ+ξ+η2Ψ(d)=νυ+ζ+ξ+η1Ψ(xυ+12,0)=Ψ(xυ+12,0)

    The edge-sums generated by the above labeling ”Ψ′” are the set of consecutive positive integers S = {ħ + 1, ħ + 2, …, ħ + q′}, where ħ = νυ2 + ζ + η. Thus by Lemma 1, ”Ψ′” can be extended to a SEMT labeling of ℧ and we obtain the magic constant a = p′ + q′ + ħ + 1, where ħ + 1 = min(S).

    For υ12 even;

    Υ(xı,ȷ)=Ψ(xı,ȷ)=Ψ(xı,ȷ);1ıυ,1ȷν

    with A′ = νυ2 + ζ + η – 1

    Ψ(xı)=Ψ(xı);1ıζ1Ψ(c2)=Ψ(c2)Ψ(zı)=Ψ(zı);1ıη1Ψ(c1)=Ψ(c1)Ψ(yı)=νυ+ζ+η+ı;1ıξ3Ψ(c3)=νυ+ζ+ξ+η2Ψ(d)=νυ+ζ+ξ+η1Ψ(xυ+12,0)=Ψ(xυ+12,0)

    The edge-sums generated by the above labeling ”Ψ′” are the set of consecutive positive integers S = {ħ′ + 1, ħ′ + 2, …, ħ′ + q′}, where ħ′ = νυ2 + ζ + η. Thus by Lemma 1, ”Ψ′” can be extended to a SEMT labeling of ℧ and we obtain the magic constant a = p′ + q′ + ħ′ + 1, where ħ′ + 1 = min(S).□

2.3 Semt Labeling and Deficiency of Forests Formed by 2-Sided Generalized Comb and Path

Definition 4

Pn be a path of order n and length n – 1, with vertices labelled from ν1 to νn along Pn and E(Pn) = {νıνı+1; 1 ≤ ın – 1}.

In the next two theorems, we will present two distinct SEMT labelings- which are non-dual of each other- for the same forest be composed of the disjoint union of path Pm and 2-sided Generalized Comb.

Theorem 4

For ν ≥ 2, υ = 2ε + 1, ε = 1, 2, 3, …

  1. Cbν,υ2 Pr is SEMT.

  2. Cbν,υ2 Pr–1 is SEMT.

  3. μs( Cbν,υ2 Pr–2) ≤ 1.

  4. μs( Cbν,υ2 Pr–3) ≤ 1; (ν, υ) ≠ (2, 3)

    where

    r=4+2υ(ν21)+2υ14+4υ24;ν0(mod2)6+2υ(ν32)+6υ14+4υ24;ν1(mod2)

Figure 5 
SEMT forest 
Cb4,52
$\begin{array}{}
\displaystyle
Cb^{2}_{4,5}
\end{array}$ ∪ P15
Figure 5

SEMT forest Cb4,52 P15

Proof

  1. Consider the graph Cbν,υ2 Pϱ

    Let p = |V()| and q = |E()|, so we get

    p=νυ+ϱ+1q=νυ+ϱ1

    where

    ϱ=r;fora(i)r1;fora(ii)

    Before formulating the labeling Ψ : V() → {1, 2, …, p}, keep in view the labeling Υ defined in Theorem 2.

    For υ12 odd;

    Take the previously mentioned labeling Υ (for υ12 odd) with A=νυ2+ϱ12. We define the labeling Ψ as follows:

    Ψ(xt)=νυ2+k;t=2k,1kϱ12νυ+νυ2+kυ+3(υ34)+2;t=2k1,1kϱ2,fora(i)νυ+νυ2+kυ+3(υ34)+1;t=2k1,1kϱ2,fora(ii)

    Ψ(xı,ȷ) = Υ(xı,ȷ) ; 1 ≤ ıυ, 1 ≤ ȷν

    Ψ(xυ+12,0)=νυ+νυ2+ϱ2υ+3(υ34)+3;fora(i)νυ+νυ2+ϱ2υ+3(υ34)+2;fora(ii)

    The edge-sums generated by the above labeling ”Ψ” are the set of consecutive positive integers S = {ħ + 1, ħ + 2, …, ħ + q}, where =νυ2+ϱ12+1. Thus by Lemma 1, ”Ψ” can be extended to a SEMT labeling of and we obtain the magic constant a = p + q + min(S), where min(S) = ħ + 1.

    For υ12 even;

    Take the labeling Υ which we have defined in Theorem 2 (for υ12 even) with A=νυ2+ϱ12. We define the labeling Ψ as follows:

    Ψ(xt)=νυ2+k;t=2k,1kϱ12νυ+νυ2+kυ+3(υ54)+3;t=2k1,1kϱ2,fora(i)νυ+νυ2+kυ+3(υ54)+2;t=2k1,1kϱ2,fora(ii)

    Ψ(xı,ȷ) = Υ(xı,ȷ); 1 ≤ ıυ, 1 ≤ ȷν

    Ψ(xυ+12,0)=νυ+νυ2+ϱ2υ+3(υ54)+4;fora(i)νυ+νυ2+ϱ2υ+3(υ54)+3;fora(ii)

    The edge-sums generated by the above labeling ”Ψ” are the set of consecutive positive integers S = {ħ′ + 1, ħ′ + 2, …, ħ′ + q}, where =νυ2+ϱ12+1. Thus by Lemma 1, ”Ψ” can be extended to a SEMT labeling of and we obtain the magic constant a = p + q + min(S), where min(S) = ħ′ + 1.

  2. Let Cbν,υ2PϱK1 , where

    V(K1)={z}

    Let p′ = |V(℧)| and q′ = |E(℧)|, so we get

    p=νυ+ϱ+2
    q=νυ+ϱ1

    where

    ϱ=r2;forb(i)r3;forb(ii)

    Before formulating the labeling Ψ′ : V(℧) → {1, 2, …, p′}, keep in view the labeling Υ defined in Theorem 2.

    For υ12 odd;

    Υ(xı,ȷ) = Ψ(xı,ȷ) = Ψ′(xı,ȷ); 1 ≤ ıυ, 1 ≤ ȷν, for b(i) and b(ii) both

    with A=νυ2+ϱ12

    Ψ(xt)=Ψ(xt),t0(mod2)Ψ(xt)=νυ+νυ2+kυ+3(υ34)+1;t=2k1,1kϱ+12,forb(i)νυ+νυ2+kυ+3(υ34);t=2k1,1kϱ+12,forb(ii)

    Let B=νυ+νυ2+ϱ+12υ+3(υ34)+1

    and C=νυ+νυ2+ϱ+12υ+3(υ34) , then

    Ψ(z)=B+1;forb(i)C+1;forb(ii)Ψ(xυ+12,0)=B+2;forb(i)C+2;forb(ii)

    The edge-sums generated by the above labeling “Ψ′” are the set of consecutive positive integers S = {ћ + 1, ћ + 2, …, ћ + q′}, where =νυ2+ϱ12+1 . Thus by Lemma 1, “Ψ′” can be extended to a SEMT labeling of ℧ and we obtain the magic constant a = p′ + q′ + min(S), where min(S) = ћ + 1.

    For υ12 even;

    Υ(xı,ȷ) = Ψ(xı,ȷ) = Ψ′(xı,ȷ); 1 ≤ ıυ, 1 ≤ ȷν, for b(i) and b(ii) both

    with A=νυ2+ϱ12

    Ψ(xt)=Ψ(xt),t0(mod2)
    Ψ(xt)=νυ+νυ2+kυ+3(υ54)+2;t=2k1,1kϱ+12,forb(i)νυ+νυ2+kυ+3(υ54)+1;t=2k1,1kϱ+12,forb(ii)

    Let B=νυ+νυ2+ϱ+12υ+3(υ54)+2

    and C=νυ+νυ2+ϱ+12υ+3(υ54)+1 , then

    Ψ(z)=B+1;forb(i)C+1;forb(ii)
    Ψ(xυ+12,0)=B+2;forb(i)C+2;forb(ii)

    The edge-sums generated by the above labeling “Ψ′” are the set of consecutive positive integers S = {ћ′ + 1, ћ′ + 2, …, ћ′ + q′}, where =νυ2+ϱ12+1 . Thus by Lemma 1, “Ψ′” can be extended to a SEMT labeling of ℧ and we obtain the magic constant a = p′ + q′ + min(S), where min(S) = ћ′ + 1. □

Theorem 5

For ν ≥ 2, υ = 2ε + 1, ε = 1, 2, 3, …

  1. Cbν,υ2 Pr is SEMT.

  2. Cbν,υ2 Pr−1 is SEMT.

  3. μs( Cbν,υ2 Pr−2) ≤ 1.

  4. μs( Cbν,υ2 Pr−3) ≤ 1.

where

r=5+2υ(ν21)+2υ14+4υ24;ν0(mod2)7+2υ(ν32)+6υ14+4υ24;ν1(mod2)

Proof

  1. Consider the graph Cbν,υ2 Pϱ

    Let p = |V()| and q = |E()|, so we get

    p=νυ+ϱ+1q=νυ+ϱ1

    where

    ϱ=r;fora(i)r1;fora(ii)

    Before formulating the labeling Ψ : V() → {1, 2, …, p}, keep in view the labeling Υ defined in Theorem 2.

    For υ12 odd;

    Take the previously mentioned labeling Υ (for υ12 odd) with A=νυ2+ϱ+12 . We define the labeling Ψ as follows:

    Ψ(xt)=νυ2+k;t=2k1,1kϱ+12νυ+νυ2+kυ+3(υ+14);t=2k,1kϱ2,fora(i)νυ+νυ2+kυ+3(υ+14)1;t=2k,1kϱ2,fora(ii)

    Ψ(xı,ȷ) = Υ(xı,ȷ) ;1 ≤ ıυ, 1 ≤ ȷν

    Ψ(xυ+12,0)=νυ+νυ2+ϱ2υ+3(υ+14)+1;fora(i)νυ+νυ2+ϱ2υ+3(υ+14);fora(ii)

    Figure 6 
SEMT forest 
Cb4,72
$\begin{array}{}
\displaystyle
Cb^{2}_{4,7}
\end{array}$ ∪ P22 ∪ K1
    Figure 6

    SEMT forest Cb4,72 P22K1

    The edge-sums generated by the above labeling “Ψ” are the set of consecutive positive integers S = {ћ + 1, ћ + 2, …, ћ + q}, where =νυ2+ϱ+12+1 . Thus by Lemma 1, “Ψ” can be extended to a SEMT labeling of and we obtain the magic constant a = p + q + min(S), where min(S) = ћ + 1.

    For υ12 even;

    Take the labeling Υ which we have defined in Theorem 2 (for υ12 even) with A=νυ2+ϱ+12 . We define the labeling Ψ as follows:

    Ψ(xt)=νυ2+k;t=2k1,1kϱ+12νυ+νυ2+kυ+3(υ14)+1;t=2k,1kϱ2,fora(i)νυ+νυ2+kυ+3(υ14);t=2k,1kϱ2,fora(ii)

    Ψ(xı,ȷ) = Υ(xı,ȷ); 1 ≤ ıυ, 1 ≤ ȷν

    Ψ(xυ+12,0)=νυ+νυ2+ϱ2υ+3(υ14)+2;fora(i)νυ+νυ2+ϱ2υ+3(υ14)+1;fora(ii)

    The edge-sums generated by the above labeling “Ψ” are the set of consecutive positive integers S = {ћ′ + 1, ћ′ + 2, …, ћ′ + q}, where =νυ2+ϱ+12+1 . Thus by Lemma 1, “Ψ” can be extended to a SEMT labeling of and we obtain the magic constant a = p + q + min(S), where min(S) = ћ′ + 1.

  2. Let ℧ ≅ Cbν,υ2 PϱK1, where

    V(K1)={z}

    Let p′ = |V(℧)| and q′ = |E(℧)|, so we get

    p=νυ+ϱ+2q=νυ+ϱ1

    where

    ϱ=r2;forb(i)r3;forb(ii)

    Before formulating the labeling Ψ′ : V(℧) → {1, 2, …, p′}, keep in view the labeling Υ defined in Theorem 2.

    For υ12 odd;

    Υ(xı,ȷ) = Ψ(xı,ȷ) = Ψ′(xı,ȷ); 1 ≤ ıυ, 1 ≤ ȷν, for b(i) and b(ii) both

    with A=νυ2+ϱ+12

    Ψ(xt)=Ψ(xt),t1(mod2)
    Ψ(xt)=νυ+νυ2+kυ+3(υ+14)1;t=2k,1kϱ12,forb(i)νυ+νυ2+kυ+3(υ+14)2;t=2k,1kϱ12,forb(ii)

    Let B=νυ+νυ2+ϱ12υ+3(υ+14)1

    and C=νυ+νυ2+ϱ12υ+3(υ+14)2 , then

    Ψ(z)=B+1;forb(i)C+1;forb(ii)
    Ψ(xυ+12,0)=B+2;forb(i)C+2;forb(ii)

    The edge-sums generated by the above labeling “Ψ′” are the set of consecutive positive integers S = {ћ + 1, ћ + 2, …, ћ + q′}, where =νυ2+ϱ+12+1 . Thus by Lemma 1, “Ψ′” can be extended to a SEMT labeling of ℧ and we obtain the magic constant a = p′ + q′ + min(S), where min(S) = ћ + 1.

    For υ12 even;

    Υ(xı,ȷ) = Ψ(xı,ȷ) = Ψ′(xı,ȷ); 1 ≤ ıυ, 1 ≤ ȷν, for b(i) and b(ii) both

    with A=νυ2+ϱ+12

    Ψ(xt)=Ψ(xt),t1(mod2)
    Ψ(xt)=νυ+νυ2+kυ+3(υ14);t=2k,1kϱ12,forb(i)νυ+νυ2+kυ+3(υ14)1;t=2k,1kϱ12,forb(ii)

    Let B=νυ+νυ2+ϱ12υ+3(υ14)

    and C=νυ+νυ2+ϱ12υ+3(υ14)1 , then

    Ψ(z)=B+1;forb(i)C+1;forb(ii)
    Ψ(xυ+12,0)=B+2;forb(i)C+2;forb(ii)

    The edge-sums generated by the above labeling “Ψ′” are the set of consecutive positive integers S = {ћ′ + 1, ћ′ + 2, …, ћ′ + q′}, where =νυ2+ϱ+12+1 . Thus by Lemma 1, “Ψ′” can be extended to a SEMT labeling of ℧ and we obtain the magic constant a = p′ + q′ + min(S), where min(S) = ћ′ + 1. □

Acknowledgement

This research is partially supported by Higher Education Commission, Pakistan.

References

[1] Kotzig A., Rosa A., Magic valuations of finite graphs, Canad. Math. Bull., 1970, 13, 451-461.10.4153/CMB-1970-084-1Search in Google Scholar

[2] Kotzig A., Rosa A., Magic valuations of complete graphs, Centre de Recherches Mathematiques, Universite de Montreal, 1972, CRM-175.Search in Google Scholar

[3] Ringle G., Lladó A.S., Another tree conjecture, Bull. Inst. Combin. Appl., 1996, 18, 83-85.Search in Google Scholar

[4] Enomoto H., Lladó A.S., T. Nakamigawa and G. Ringel, Super edge-magic graphs, SUT J. Math., 1998, 34(2), 105-109.10.55937/sut/991985322Search in Google Scholar

[5] Wallis W.D., Magic graphs, Birkhäuser, Boston-Basel-Berlin, 2001.10.1007/978-1-4612-0123-6Search in Google Scholar

[6] Lee S.M., Shah Q.X., All trees with at most 17 vertices are super edge magic, 2002, 16th MCCCC Conference, Carbondale, University Southern Illinois, Nov. 2002.Search in Google Scholar

[7] Javed S., Hussain M., Riasat A., Kanwal S., Imtiaz M., Ahmad M.O., Deficiencies of forests, Open Math., 2017, 15, 1431-1439.10.1515/math-2017-0122Search in Google Scholar

[8] Figueroa-Centeno R.M., Ichishima R., Muntaner-Batle F.A., The place of super edge-magic labeling among other classes of labeling, Discrete Math., 2001, 231, 153-168.10.1016/S0012-365X(00)00314-9Search in Google Scholar

[9] Avadayappan S., Vasuki R., Jeyanthi P., Magic Strength of a Graph, Indian J. pure appl. Math., 2000, 31(7), 873-883.Search in Google Scholar

[10] Avadayappan S., Jeyanthi P., Vasuki R., Super magic strength of a graph, Indian J. pure appl. Math., 2001, 32(11), 1621-1630.Search in Google Scholar

[11] Swamminatan V., Jeyanthi P., Super edge-magic strength of fire crackers, banana trees and unicyclic graphs, Discrete Math., 2006, 306, 1624-1636.10.1016/j.disc.2005.06.038Search in Google Scholar

[12] Akka D.G., Warad N.S., Super magic strength of a graph, Indian J. Pure Appl. Math., 2010, 41(4), 557-568.10.1007/s13226-010-0031-zSearch in Google Scholar

[13] Hungund N.S., Akka D.G., Super edge-magic strength of some new families of graphs, Bull. Marathwada Math. Soc., 2011, 12(1), 47-54.Search in Google Scholar

[14] Figueroa-Centeno R.M., Ichishima R., Muntaner-Batle F.A., On the Super Edge-Magic Deficiency of Graphs, Ars Combin., 2006, 78, 33-45.10.1016/S1571-0653(04)00074-5Search in Google Scholar

[15] Figueroa-Centeno R.M., Ichishima R., Muntaner-Batle F.A., On the super edge-magic deficiency of graphs, Electron. Notes Discrete Math., 2002, 11, 299-314.10.1016/S1571-0653(04)00074-5Search in Google Scholar

[16] Ngurah A.A., Baskoro E.T., Simanjuntak R., On the super edge-magic deficiencies of graphs, Australas. J. Combin., 2008, 40, 3-14.10.1007/978-3-540-89550-3_16Search in Google Scholar

[17] Baig A.Q., Ahmad A., Baskoro E.T., Simanjuntak R., On the super edge-magic deficiency of forests, Util. Math., 2011, 86, 147-159.Search in Google Scholar

[18] Javed S., Riasat A., Kanwal S., On super edge magicness and deficiencies of forests, Utilitas Math., 2015, 98, 149-169.Search in Google Scholar

[19] Figueroa-Centeno R.M., Ichishima R., Muntaner-Batle F.A., Some new results on the super edge-magic deficiency of graphs, J. Combin. Math. Combin. Comput., 2005, 55, 17-31.Search in Google Scholar

[20] Kanwal S., Kanwal I., SEMT Valuations of Disjoint Union of Combs, Stars and Banana Trees, Punjab Univ. J. Math., 2018, 50(3), 131-144.Search in Google Scholar

[21] Kanwal S., Riasat A., Imtiaz M., Iftikhar Z., Javed S., Ashraf R., Bounds of Strong EMT Strength for certain Subdivision of Star and Bistar, Open Math., 2018, 16, 1313-1325.10.1515/math-2018-0111Search in Google Scholar

[22] S. Kanwal S., Azam A., Iftikhar Z., SEMT Labelings and Deficiencies of Forests with Two Components (II), Punjab Univ. J. Math., 2019, 51(4), 1-12.Search in Google Scholar

[23] Kanwal S., Iftikhar Z., Azam A., SEMT Labelings and Deficiencies of Forests with Two Components (I), Punjab Univ. J. Math., 2019, 51(5), 137-149.Search in Google Scholar

[24] Gallian J.A., A dynamic survey of graph labeling, Electron. J. Combin., 19th edition, Dec. 2016, DS6.10.37236/11668Search in Google Scholar

[25] Bača M., Miller M., Super edge-antimagic graphs (a wealth of problems and some solutions), 2008, Brown Walker Press, Boca Raton, Florida, USA.Search in Google Scholar

[26] West D.B., Introduction to Graph Theory, second edition, 2001, Prentice-Hall.Search in Google Scholar

[27] Baskoro E.T., I. W. Sundarsana and Y. M. Cholily, How to construct new super edge-magic graphs from some old ones, J. Indones. Math. Soc., (MIHMI), 2005, 11, 155-162.Search in Google Scholar

Received: 2018-07-05
Accepted: 2019-03-18
Published Online: 2019-05-30

© 2019 Kanwal et al., published by De Gruyter

This work is licensed under the Creative Commons Attribution 4.0 Public License.

Articles in the same Issue

  1. Regular Articles
  2. On the Gevrey ultradifferentiability of weak solutions of an abstract evolution equation with a scalar type spectral operator of orders less than one
  3. Centralizers of automorphisms permuting free generators
  4. Extreme points and support points of conformal mappings
  5. Arithmetical properties of double Möbius-Bernoulli numbers
  6. The product of quasi-ideal refined generalised quasi-adequate transversals
  7. Characterizations of the Solution Sets of Generalized Convex Fuzzy Optimization Problem
  8. Augmented, free and tensor generalized digroups
  9. Time-dependent attractor of wave equations with nonlinear damping and linear memory
  10. A new smoothing method for solving nonlinear complementarity problems
  11. Almost periodic solution of a discrete competitive system with delays and feedback controls
  12. On a problem of Hasse and Ramachandra
  13. Hopf bifurcation and stability in a Beddington-DeAngelis predator-prey model with stage structure for predator and time delay incorporating prey refuge
  14. A note on the formulas for the Drazin inverse of the sum of two matrices
  15. Completeness theorem for probability models with finitely many valued measure
  16. Periodic solution for ϕ-Laplacian neutral differential equation
  17. Asymptotic orbital shadowing property for diffeomorphisms
  18. Modular equations of a continued fraction of order six
  19. Solutions with concentration and cavitation to the Riemann problem for the isentropic relativistic Euler system for the extended Chaplygin gas
  20. Stability Problems and Analytical Integration for the Clebsch’s System
  21. Topological Indices of Para-line Graphs of V-Phenylenic Nanostructures
  22. On split Lie color triple systems
  23. Triangular Surface Patch Based on Bivariate Meyer-König-Zeller Operator
  24. Generators for maximal subgroups of Conway group Co1
  25. Positivity preserving operator splitting nonstandard finite difference methods for SEIR reaction diffusion model
  26. Characterizations of Convex spaces and Anti-matroids via Derived Operators
  27. On Partitions and Arf Semigroups
  28. Arithmetic properties for Andrews’ (48,6)- and (48,18)-singular overpartitions
  29. A concise proof to the spectral and nuclear norm bounds through tensor partitions
  30. A categorical approach to abstract convex spaces and interval spaces
  31. Dynamics of two-species delayed competitive stage-structured model described by differential-difference equations
  32. Parity results for broken 11-diamond partitions
  33. A new fourth power mean of two-term exponential sums
  34. The new operations on complete ideals
  35. Soft covering based rough graphs and corresponding decision making
  36. Complete convergence for arrays of ratios of order statistics
  37. Sufficient and necessary conditions of convergence for ρ͠ mixing random variables
  38. Attractors of dynamical systems in locally compact spaces
  39. Random attractors for stochastic retarded strongly damped wave equations with additive noise on bounded domains
  40. Statistical approximation properties of λ-Bernstein operators based on q-integers
  41. An investigation of fractional Bagley-Torvik equation
  42. Pentavalent arc-transitive Cayley graphs on Frobenius groups with soluble vertex stabilizer
  43. On the hybrid power mean of two kind different trigonometric sums
  44. Embedding of Supplementary Results in Strong EMT Valuations and Strength
  45. On Diophantine approximation by unlike powers of primes
  46. A General Version of the Nullstellensatz for Arbitrary Fields
  47. A new representation of α-openness, α-continuity, α-irresoluteness, and α-compactness in L-fuzzy pretopological spaces
  48. Random Polygons and Estimations of π
  49. The optimal pebbling of spindle graphs
  50. MBJ-neutrosophic ideals of BCK/BCI-algebras
  51. A note on the structure of a finite group G having a subgroup H maximal in 〈H, Hg
  52. A fuzzy multi-objective linear programming with interval-typed triangular fuzzy numbers
  53. Variational-like inequalities for n-dimensional fuzzy-vector-valued functions and fuzzy optimization
  54. Stability property of the prey free equilibrium point
  55. Rayleigh-Ritz Majorization Error Bounds for the Linear Response Eigenvalue Problem
  56. Hyper-Wiener indices of polyphenyl chains and polyphenyl spiders
  57. Razumikhin-type theorem on time-changed stochastic functional differential equations with Markovian switching
  58. Fixed Points of Meromorphic Functions and Their Higher Order Differences and Shifts
  59. Properties and Inference for a New Class of Generalized Rayleigh Distributions with an Application
  60. Nonfragile observer-based guaranteed cost finite-time control of discrete-time positive impulsive switched systems
  61. Empirical likelihood confidence regions of the parameters in a partially single-index varying-coefficient model
  62. Algebraic loop structures on algebra comultiplications
  63. Two weight estimates for a class of (p, q) type sublinear operators and their commutators
  64. Dynamic of a nonautonomous two-species impulsive competitive system with infinite delays
  65. 2-closures of primitive permutation groups of holomorph type
  66. Monotonicity properties and inequalities related to generalized Grötzsch ring functions
  67. Variation inequalities related to Schrödinger operators on weighted Morrey spaces
  68. Research on cooperation strategy between government and green supply chain based on differential game
  69. Extinction of a two species competitive stage-structured system with the effect of toxic substance and harvesting
  70. *-Ricci soliton on (κ, μ)′-almost Kenmotsu manifolds
  71. Some improved bounds on two energy-like invariants of some derived graphs
  72. Pricing under dynamic risk measures
  73. Finite groups with star-free noncyclic graphs
  74. A degree approach to relationship among fuzzy convex structures, fuzzy closure systems and fuzzy Alexandrov topologies
  75. S-shaped connected component of radial positive solutions for a prescribed mean curvature problem in an annular domain
  76. On Diophantine equations involving Lucas sequences
  77. A new way to represent functions as series
  78. Stability and Hopf bifurcation periodic orbits in delay coupled Lotka-Volterra ring system
  79. Some remarks on a pair of seemingly unrelated regression models
  80. Lyapunov stable homoclinic classes for smooth vector fields
  81. Stabilizers in EQ-algebras
  82. The properties of solutions for several types of Painlevé equations concerning fixed-points, zeros and poles
  83. Spectrum perturbations of compact operators in a Banach space
  84. The non-commuting graph of a non-central hypergroup
  85. Lie symmetry analysis and conservation law for the equation arising from higher order Broer-Kaup equation
  86. Positive solutions of the discrete Dirichlet problem involving the mean curvature operator
  87. Dislocated quasi cone b-metric space over Banach algebra and contraction principles with application to functional equations
  88. On the Gevrey ultradifferentiability of weak solutions of an abstract evolution equation with a scalar type spectral operator on the open semi-axis
  89. Differential polynomials of L-functions with truncated shared values
  90. Exclusion sets in the S-type eigenvalue localization sets for tensors
  91. Continuous linear operators on Orlicz-Bochner spaces
  92. Non-trivial solutions for Schrödinger-Poisson systems involving critical nonlocal term and potential vanishing at infinity
  93. Characterizations of Benson proper efficiency of set-valued optimization in real linear spaces
  94. A quantitative obstruction to collapsing surfaces
  95. Dynamic behaviors of a Lotka-Volterra type predator-prey system with Allee effect on the predator species and density dependent birth rate on the prey species
  96. Coexistence for a kind of stochastic three-species competitive models
  97. Algebraic and qualitative remarks about the family yy′ = (αxm+k–1 + βxmk–1)y + γx2m–2k–1
  98. On the two-term exponential sums and character sums of polynomials
  99. F-biharmonic maps into general Riemannian manifolds
  100. Embeddings of harmonic mixed norm spaces on smoothly bounded domains in ℝn
  101. Asymptotic behavior for non-autonomous stochastic plate equation on unbounded domains
  102. Power graphs and exchange property for resolving sets
  103. On nearly Hurewicz spaces
  104. Least eigenvalue of the connected graphs whose complements are cacti
  105. Determinants of two kinds of matrices whose elements involve sine functions
  106. A characterization of translational hulls of a strongly right type B semigroup
  107. Common fixed point results for two families of multivalued A–dominated contractive mappings on closed ball with applications
  108. Lp estimates for maximal functions along surfaces of revolution on product spaces
  109. Path-induced closure operators on graphs for defining digital Jordan surfaces
  110. Irreducible modules with highest weight vectors over modular Witt and special Lie superalgebras
  111. Existence of periodic solutions with prescribed minimal period of a 2nth-order discrete system
  112. Injective hulls of many-sorted ordered algebras
  113. Random uniform exponential attractor for stochastic non-autonomous reaction-diffusion equation with multiplicative noise in ℝ3
  114. Global properties of virus dynamics with B-cell impairment
  115. The monotonicity of ratios involving arc tangent function with applications
  116. A family of Cantorvals
  117. An asymptotic property of branching-type overloaded polling networks
  118. Almost periodic solutions of a commensalism system with Michaelis-Menten type harvesting on time scales
  119. Explicit order 3/2 Runge-Kutta method for numerical solutions of stochastic differential equations by using Itô-Taylor expansion
  120. L-fuzzy ideals and L-fuzzy subalgebras of Novikov algebras
  121. L-topological-convex spaces generated by L-convex bases
  122. An optimal fourth-order family of modified Cauchy methods for finding solutions of nonlinear equations and their dynamical behavior
  123. New error bounds for linear complementarity problems of Σ-SDD matrices and SB-matrices
  124. Hankel determinant of order three for familiar subsets of analytic functions related with sine function
  125. On some automorphic properties of Galois traces of class invariants from generalized Weber functions of level 5
  126. Results on existence for generalized nD Navier-Stokes equations
  127. Regular Banach space net and abstract-valued Orlicz space of range-varying type
  128. Some properties of pre-quasi operator ideal of type generalized Cesáro sequence space defined by weighted means
  129. On a new convergence in topological spaces
  130. On a fixed point theorem with application to functional equations
  131. Coupled system of a fractional order differential equations with weighted initial conditions
  132. Rough quotient in topological rough sets
  133. Split Hausdorff internal topologies on posets
  134. A preconditioned AOR iterative scheme for systems of linear equations with L-matrics
  135. New handy and accurate approximation for the Gaussian integrals with applications to science and engineering
  136. Special Issue on Graph Theory (GWGT 2019)
  137. The general position problem and strong resolving graphs
  138. Connected domination game played on Cartesian products
  139. On minimum algebraic connectivity of graphs whose complements are bicyclic
  140. A novel method to construct NSSD molecular graphs
Downloaded on 15.9.2025 from https://www.degruyterbrill.com/document/doi/10.1515/math-2019-0044/html
Scroll to top button