Startseite 2-closures of primitive permutation groups of holomorph type
Artikel Open Access

2-closures of primitive permutation groups of holomorph type

  • Xue Yu und Jiangmin Pan EMAIL logo
Veröffentlicht/Copyright: 31. Juli 2019

Abstract

The 2-closure G(2) of a permutation group G on a finite set Ω is the largest subgroup of Sym(Ω) which has the same orbits as G in the induced action on Ω × Ω. In this paper, the 2-closures of certain primitive permutation groups of holomorph simple and holomorph compound types are determined.

MSC 2010: 05C25; 20B15; 20B30

1 Introduction

Let G be a permutation group on a finite set Ω. Then G has a natural induced action on Ω(2) := Ω × Ω as follows:

(α,β)g=(αg,βg),whereα,βΩ,gG.

Each orbit of G of the above action is called an orbital of G on Ω. We denote by Orbl(G, Ω) the set of all orbitals of G on Ω.

In 1969, Wielandt [1] defined the 2-closure of G to be the group

G(2):={xSym(Ω)Ox=OforeachOOrbl(G,Ω)},

namely the largest subgroup of Sym(Ω) that has the same orbitals of G. Clearly, G(2)G. If G = G(2), then G is called 2-closed. See some basic properties of 2-closures in Wielandt [1, 2].

A transitive permutation group G ≤ Sym(Ω) is called primitive if the vertex stabilizer Gα := {gG | αg = α} is maximal in G. Denote by soc(G) the socle of G, namely the product of all minimal normal subgroups of G. Then either soc(G) is a minimal normal subgroup of G, or soc(G) = M × N with MN being minimal normal subgroups of G. According to the structure and the action of soc(G), the well-known O’Nan-Scott theorem divided the finite primitive permutation groups into eight types, refer to [3, 4, 5]. The eight types are described as follows:

HA (Holomorph Affine): soc(G) ≅ Zpl is regular on Ω and X Zpl : GL(l, p), where p is a prime and l ≥ 1;

HS (Holomorph Simple): soc(G) = M × N, where MNT are nonabelian simple normal subgroups of X and regular on Ω;

HC (Holomorph Compound): soc(G) = M × N, where MNTk are minimal normal subgroups of X and regular on Ω with T nonabelian simple and k ≥ 2;

AS (Almost simple): soc(G) = T is a nonabelian simple group and not regular on Ω, and TG ≤ Aut(T);

SD (Simple Diagonal): soc(G) ≅ Tl is a minimal normal subgroup of G, with l ≥ 2 and T is nonabelian simple, (soc(G))α = {(t, ⋯, t) | tT} ≅ T for αΩ, and GTl.(Out(T) × Sl);

CD (Compound Diagonal): soc(G) ≅ Tl with l ≥ 4 and T nonabelian simple, and (soc(G))αTk with k ≥ 2 and k | l;

TW (Twisted Wreath Product): soc(G) ≅ Tl is regular on Ω and Gα is insoluble, where T is nonabelian simple and l ≥ 6;

PA (Product Action): soc(G) ≅ Tl is a minimal normal subgroup of X with T nonabelian simple and l ≥ 2, and G ≤ Aut(T) ≀ Sl; moreover, there exists a set Δ such that Ω = Δl, Aut(T) acts irregularly on Δ and G acts on Δl as follows: for (w1, …, wl) ∈ Ωl, (h1, …, hl) ∈ Aut(T)l and σ ∈ Sl,

(w1,,wl)(h1,,hl)σ=(w1σ1h1σ1,,wlσ1hlσ1).

In 1988, Liebeck, Praeger and Saxl [6] studied the 2-closures of simply primitive (namely primitive but not 2-transitive) permutation groups of almost simple type, and proved that if G is a such group with socle T, then either TG(2) ≤ Aut(T) or (G, G(2)) is given in an explicit list. For more results regarding primitive groups and their 2-closures, see [7, 8, 9, 10, 11, 12, 13]. The main purpose of this paper is to determine the 2-closures of certain primitive permutation groups of HS and HC types; for convenience both types are called holomorph type.

The notations used in this paper are standard. For example, for a positive integer n, we denote by ℤn the cyclic group of order n, and by Sn the symmetric group of degree n. Given two groups N and H, denote by N × H the direct product of N and H, by N.H an extension of N by H, and if such an extension is split, then we write N : H instead of N.H. Also, we denote by Gn the direct product of the group G of n terms, and by HP the wreath product of groups H and P.

The main results of this paper are as follows.

Theorem 1.1

Let G = T : Aut(T) be a primitive permutation group of type HS on Ω, where T is a nonabelian simple group. Then the following statements hold:

  1. If there exists tT which is not conjugate to t–1 in Aut(T), then G(2) = G.

  2. If each tT is conjugate to t–1 in Aut(T), then G(2) = G.ℤ2 is primitive of type SD.

Theorem 1.2

Let G = N : Aut(N) be a primitive permutation group of type HC on Ω, where NTd with T a nonabelian simple group and d ≥ 2. Then the following statements hold:

  1. If there exists tT which is not conjugate to t–1 in Aut(T), then G(2) = G.

  2. If each tT is conjugate to t–1 in Aut(T), then

    G(2)=[T2.(Out(T)×Z2)]d.Sd

    is primitive of type CD.

After this introductory section, we explain the actions of certain primitive permutation groups in Section 2, and complete the proofs of Theorems 1.1 and 1.2 in Section 3.

2 Actions of primitive permutation groups

In this section, we explain the actions of primitive permutation groups of several types that will be used in Section 3. The main contents of this section can be found in Giudici, Li and Praeger [14, Section 2] and Liebeck, Praeger and Saxl [15].

For a group G, denote by

G^={g^g^:xxg,for allg,xG},
Gˇ={g^g^:xg1x,for allg,xG}

the right regular representation and the left regular representation of G, respectively. Clearly, both Ĝ and Ǧ can be viewed as regular (permutation) subgroups on G, and centralize other.

Let H be a subgroup of G, and denote by [G : H] the set of cosets of H in G. The coset action of G on [G : H] is defined as follows:

(Hg)x=Hgx,forg,xG.

It is well known each transitive action of a group X on a set Ω can be identified (permutation equivalent) with the coset action of X on [X : Xα] with αΩ. In particular, if X is regular on Ω, then Xα = 1, and the action of X on Ω can be identified with the right regular representation (and so Ω can be identified with X).

In the following, we give several remarks on the actions of primitive permutation groups of several types. Let G ≤ Sym(Ω) be a primitive permutation group, and let N = soc(G).

Remark 1

Assume that G is of type HS or HC. Then N = M1 × M2, where M1M2Td with d ≥ 1 are nonabelian minimal normal subgroups of G and regular on Ω, and GNSym(Ω)(N) = N : Aut(N). Moreover, the action of G on Ω as follows:

xnσ=(xn)σ=xσnσ,

where xΩ, nN and σ ∈ Aut(N).

On the other hand, since M1Td is regular on Ω, we may identify Ω = Td and identify the action of M1 on Ω with the right regular representation d, hence M2 = CG(M1) can be identified with Ťd. Consequently, we obtain

G(Td^×Tdˇ).(Out(T)dSd),

and the action of G on Ω = Td is as follows:

(t1,t2,,td)(g1,g2,,gd)^=(t1g1,t2g2,,tdgd),(t1,t2,,td)(g1,g2,,gd)ˇ=(g11t1,g21t2,,gd1td),(t1,t2,,td)(σ1,σ2,,σd)=(t1σ1,t2σ2,,tdσd),(t1,t2,,td)τ=(t1τ1,t2τ1,,tdτ1),

where (t1, t2, …, td), (g1, g2, …, gd) ∈ Td, (σ1, σ2, …, σd) ∈ Out(T)d and τ ∈ Sd.

Remark 2

Assume that G is of type SD and N = soc(G) = T2, with T a nonabelian simple group. Then Nα = {(t, t, …, t) | tT} ≅ T for αΩ, and

GT2.(Out(T)×S2)Aut(T2).

Since there is an one to one correspondence between [N : Nα] to T via Nα(t1,t2)t11t2, we may identify Ω with T. Now, for tΩ, we easily conclude that the action of G on Ω is as following (or see [15, P. 307]):

t(t1,t2)=t11tt2for(t1,t2)T2,t(α,α)=tαfor(α,α)Out(T),t(12)=t1for(12)S2.

Remark 3

Assume that G is of type HC or CD and N = soc(G) = Td, with T a nonabelian simple group and d ≥ 4. Then G can be built from a primitive permutation group of type HS or SD respectively by product action, see [14, P. 296]. Hence there exists a set Δ, and a primitive permutation group H of type HS or SD on Δ, such that Ω = Δk for some k | d and GH ≀ Sk = Hk : Sk, and G acts on Δk in product action.

3 Proofs of Theorems 1.1 and 1.2

In this section, we prove Theorem 1.1 and Theorem 1.2. We first give an observation.

Lemma 3.1

Let G = Td : Aut(Td) be a primitive permutation group of type HC on Ω. We may identify Δ = Td (see Remark 1 in Section 2). Then the vertex stabilizer G1 := {gG | 1g = 1} = Aut(Td), where 1 is the identity element of Td.

Proof

Let G, where gTd and σ ∈ Aut(Td). By Remark 1, we have 1 = gσ. Hence G1 if and only gσ = 1, or equivalently g = 1. The lemma follows.□

Proof of Theorem 1.1

Suppose that G = T : Aut(T) is a primitive permutation group of type HS on Ω, where T is a nonabelian simple group. Since G(2) is an overgroup of G, by Praeger [3, Proposition 8.1], either G(2) = An or Sn with n = |Ω|, or soc(G(2)) = soc(G) = T2 and G(2) is of type HS or SD.

If G(2) = An or Sn, then G(2) is 2-transitive on Ω, hence G(2) and so G has exactly two orbitals, namely G is 2-transitive, which is a contradiction as a well known theorem of Burnside (see [16, Theorem 4.1B]) states that a 2-transitive permutation group is either of type HA or AS.

Therefore, G(2) is of type HS or of type SD and soc(G(2)) = soc(G) = T2. Consequently, we always have GG(2)G : S2. Since T is regular on Ω, we may identify Ω = T.

Assume first that there exists an element tT which is not conjugate to t–1 in Aut(T). Let O1 = {(1, t)G and O2 = (1, t–1)G be two orbitals of G on Ω. If O1 = O2, then (1, t) = (1, t–1)x = (1x, (t–1)x) for some xG. It follows that t = (t–1)x and 1x = 1. Thus xG1 = Aut(T) by Lemma 3.1, and t is conjugate to t–1 in Aut(T), a contradiction.

Therefore, O1O2. For each tT and (12) ∈ S2, we have t(12) = t–1 by Remark 2 in Section 2, it follows

O1(12)=(1,t)G(12)=(1,t)(12)G=(1,t1)G=O2,

that is, (12) ∉ G(2). Hence G(2) = G, part (i) of Theorem 1.1 holds.

Now assume that each element tT is conjugate to t–1 in Aut(T). By the transitivity of G on Ω, each orbital of G on Ω can be expressed as (1, t)G for some tT. By assumption, there is α ∈ Aut(T) ≤ G such that tα = t–1. By Remark 2, it follows that

((1,t)G)(12)=(1,t)G(12)=(1,t)(12)G=(1,t1)G=(1,t)αG=(1,t)G,

that is, (12) ∈ G(2). Hence G(2) = G.2, part (ii) of Theorem 1.1 holds. This completes the proof of Theorem 1.1.□

Now, we complete the proof of Theorem 1.2.

Proof of Theorem 1.2

Suppose that G = N : Aut(N) is a primitive permutation group of type HC on Ω, where N = Td with T a nonabelian simple group and d ≥ 2. Since G(2) is an overgroup of G and soc(G) = T2d with 2d ≥ 4, by Praeger [3, Proposition 8.1], either G(2) = An or Sn with n = |Ω|, or soc(G(2)) = soc(G) and G(2) is a primitive permutation group of type HC or CD.

If G(2) = An or Sn, then G is 2-transitive on Ω, and so is G since G and G(2) have the same orbitals, by a theorem of Burnside (see [16, Theorem 4.1B]), G is of type HA or AS, a contradiction.

Thus G(2) is a primitive permutation group of type HC or CD, and soc(G(2)) = soc(G) = T2d. By Remark 3, it easily follows that there exists a set Δ and a primitive permutation group H of type SD on Δ with soc(H) = T2, such that Ω = Δd, and GG(2)H ≀ Sd = Hd : Sd, and G(2) acts on Δd in product action. Notice that T2HT2.(Out(T) × S2).

Notice that H is a primitive permutation group of type SD on Δ with socle T2, (soc(H))δ = {(t, t) | tT} ≅ T for each δΔ, soc(H) has a normal subgroup T which is regular on Δ. Thus we may identify Δ = T, and hence identify Ω = Td. Let O be an orbital of G, and let 1 = (1, 1, …, 1) ∈ Td = Ω. By the vertex transitivity of G, we may assume O = (1, γ)G, where γ = (t1, t2, …, td) ∈ Td = Ω.

Now, we prove that part (i) and part (ii) of Theorem 1.2 are true respectively.

  1. Suppose G(2) > G. Then there is xG(2)G. Since G(2)H ≀ Sd = Hd : Sd, we may set x = (h1, h2, …, hd)τ, where hiHi with 1 ≤ id and τ ∈ Sd. Since H is primitive of type SD with socle T2, we may write hi = ξi(ui1, ui2)σi, where (ui1, ui2) ∈ T2, σi ∈ Out(T) and ξi ∈ S2. By Remarks 2 and 3, we conclude

    (1,γ)x=(1x,γx)=(1(h1,h2,...,hd)τ,(t1,t2,...,td)(h1,h2,...,hd)τ)=(1,(t1,t2,...,td))(ξ1(u11,12)σ1,ξ2(u21,22)σ2,...,ξd(ud1,d2)σd)τ.

    If ξi = 1 for each i ∈ {1, 2, …, d}, then xG, a contradiction. Hence without loss of the generality, we may assume ξ1 ≠ 1. Then

    (1,γ)x=(1,(t1ξ1,t2ξ2,...,tdξd))((u11,u12)σ1,(u21,u22)σ2,...,(ud1,ud2)σd)τ=(1,(t11,t2ϵ2,...,tdϵd))((u11,u12)σ1,(u21,u22)σ2,...,(ud1,ud2)σd)τ,

    where ϵi = 1 if ξi = 1, and ϵi = –1 if ξi ≠ 1 with 1 ≤ id.

    Let g0 := ((u11, u12)σ1, (u21, u22)σ2, …, (ud1, ud2)σd)τG. Then

    (1,(t11,t2ϵ2,...,tdϵd))=(1,(t11,t2ϵ2,...,tdϵd))g0g01(1,γ)G

    and (1, γ)x ∈ (1, γ)G. Hence

    (1,(t11,t2ϵ2,...,tdϵd))=(1,(t1,t2,...,td))y=(1y,(t1,t2,...,td)y)

    for some yG. So 1y = 1, and hence yG1 = Aut(T)d by lemma 3.1. It follows that y = (η1, η2, …, ηd), where ηi ∈ Aut(T)i with 1 ≤ id. Thus (t11,t2ϵ2,...,tdϵd)=(t1,t2,...,td)y=(t1η1,t2η2,...,tdηd). Hence t11=t1η1. That is, t1 is conjugate to t11 in Aut(T), part (i) of Theorem 1.2 holds.

  2. Suppose that each tT is conjugate to t–1 in Aut(T). Note that G(2)HSd ≤ (T2(Out(T) × S2)) ≀ Sd, we only need to prove T2(Out(T) × S2)] ≀ SdG. For any

    x=(ξ1(u11,u12)σ1,ξ2(u21,u22)σ2,...,ξd(ud1,ud2)σd)[T2.(Out(T)×S2)]d,

    where ξiS2, (ui1, ui2) ∈ T2 and σi ∈ Out(T) with 1 ≤ id, it is easy to see that Ox = O if and only if (1, γ)gxO for each gG. Notice that

    gx=g(ξ1(u11,u12)σ1,ξ2(u21,u22)σ2,...,ξd(ud1,ud2)σd)=g(ξ1,ξ2,...,ξd)((u11,u12)σ1,(u21,u22)σ2,...,(ud1,ud2)σd)=g((u11,u12)σ1,(u21,u22)σ2,...,(ud1,ud2)σd)(ξ1,ξ2,...,ξd)

    for some (ui1,ui2)σiT2. Out(T) with 1 ≤ id. Set

    g:=g((u11,u12)σ1,(u21,u22)σ2,...,(ud1,ud2)σd).

    Then g′ ∈ G. It follows that gx = g′(ξ1, ξ2, …, ξd). Note that g′ ∈ G = Kd.Sd = (T2.Out(T))d.Sd, then g = (τ1, τ2, …, τd)π, where τiK, πP with 1 ≤ id. Thus

    (1,γ)gx=(1,γ)g(ξ1,ξ2,...,ξd)=(1,(t1,t2,...,td))g(ξ1,ξ2,...,ξd)=(1,(t1τ1,t2τ2,...,tdτd)π)(ξ1,ξ2,...,ξd)=(1,(t1π1τ1π1,t2π1τ2π1,...,tdπ1τdπ1))(ξ1,ξ2,...,ξd)={1,((t1π1τ1π1)ξ1,(t2π1τ2π1)ξ2,...,(tdπ1τdπ1)ξd)}=(1,((t1π1ξ1)τ1π1,(t2π1ξ2)τ2π1,...,(tdπ1ξd)τdπ1))=(1,((t1π1ϵ1)τ1π1,(t2π1ϵ2)τ2π1,...,(tdπ1ϵd)τdπ1))=(1,((t1ϵ1)τ1,(t2ϵ2)τ2,...,(tdϵd)τd)π)=(1,((t1ϵ1)τ1,(t2ϵ2)τ2,...,(tdϵd)τd))π=(1,(t1ϵ1,t2ϵ2,...,tdϵd))(τ1,τ2,...,τd)π,

    where (tiπ1τiπ1)ξi=tiπ1τiπ1ifξi=1,and(tiπ1τiπ1)ξi=(tiπ1τiπ1)1=(tiπ11)τiπ1ifξi1. Since t is conjugate to t–1 in Aut(T) for each tT, it follows that tiηi=tiϵi for some ηi ∈ Aut(T) with 1 ≤ id. Then

    (1,γ)gx=[1,(t1η1,t2η2,...,tdηd)]g=[1,(t1,t2,...,td)](η1,η2,...,ηd)g=(1,γ)(η1,η2,...,ηd)g.

    Note that (η1, η2, …, ηd)g′ ∈ G1 = Aut(T)dG, it follows that (1, γ)gx ∈ (1, γ)G. Thus xG and hence G(2) = [T2.(Out(T) × S2)]d.Sd. This completes the proof of Theorem 1.2.□

Acknowledgements

The authors thank Professor Cai Heng Li for some helpful discussions, and thank the referee for helpful comments.

This work was supported by the NSFC (11231008, 11861076), the Scientific Research Fund of Yunnan Education Department (2018Y008) and the NSF of Yunnan Province (2019FB-2).

References

[1] Wielandt H., Permutation groups through invariant relations and invariant functions, Lecture Notes, 1969, Columbus: Ohio State University; also published in Wielandt H., Mathematische Werke/Mathematical works, Vol. 1, Group theory, Berlin, Walter de Gruyter & Co., 1994, 237–296.Suche in Google Scholar

[2] Wielandt H., Mathematische Werke/Mathematical works, Vol. 1, Group theory, Berlin: Walter de Gruyter & Co., 1994, 237–296.10.1515/9783110863383Suche in Google Scholar

[3] Praeger C.E., The inclusion problem for finite primitive permutation groups, Proc. London Math. Soc. 1990, 50(3), 68–88.10.1112/plms/s3-60.1.68Suche in Google Scholar

[4] Praeger C.E., Finite transitive permutation groups and vertex-transitive graphs, Graph symmetry: Algebraic methods and applications (ed. G. Hahn and G. Sabidussi), NATO Advanced Science Institue Series C 497 (Klumer, Dordrecht, 1997), 277–318.10.1007/978-94-015-8937-6_7Suche in Google Scholar

[5] Liebeck M.W., On the O’Nan-Scott theorem for finite primitive permutation groups, J. Austral. Math. Soc., 1988, 44(A), 389–396.10.1017/S144678870003216XSuche in Google Scholar

[6] Liebeck M.W., Praeger C.E., Saxl J., On the 2-closures of finite permutation groups, J. London Math. Soc., 1988, 37(2), 241–252.10.1112/jlms/s2-37.2.241Suche in Google Scholar

[7] Evdokimov S.A., Ponomarenko I.N., Characterization of cyclotomic schemes and normal Schur rings over a cyclic group, Algebra iAnaliz, 2002, 14, 11–55.Suche in Google Scholar

[8] Evdokimov S.A., Ponomarenko I.N., Two-closure of odd permutation group in polynomial time, Discrete Math., 2001, 235, 221–232.10.1016/S0012-365X(00)00275-2Suche in Google Scholar

[9] Praeger C.E., Saxl J., Closures of finite primitive permutation groups, Bull. London Math. Soc., 1992, 24, 251–258.10.1112/blms/24.3.251Suche in Google Scholar

[10] Xu J., On closures of finite permutation group (PhD thesis), The University of Western Australia, 2006.10.1017/S0004972700047547Suche in Google Scholar

[11] Xu J., Digraph representations of 2-closed permutation groups with a normal regular cyclic subgroup, Electron. J. Combin., 2015, 22, 4–31.10.37236/5146Suche in Google Scholar

[12] O’Nan M.E., Estimation of Sylow subgroups in primitive permutation groups, Math. Z., 1976, 147, 101–111.10.1007/BF01164276Suche in Google Scholar

[13] Praeger C.E., On elements of prime order in primitive permutation groups, J. Algebra, 1979, 60, 126–157.10.1016/0021-8693(79)90111-XSuche in Google Scholar

[14] Giudici. M., Li C.H., Praeger C.E., Analysing finite locally s-arc transitive graphs, Trans. Amer. Math. Soc., 2003, 356, 291–317.10.1090/S0002-9947-03-03361-0Suche in Google Scholar

[15] Liebeck M.W., Praeger C.E., Saxl J., Transitive subgroups of primitive permutation groups, J. Algebra, 2000, 234, 291–361.10.1006/jabr.2000.8547Suche in Google Scholar

[16] Dixon J.D., Mortimer B., Permutation Groups, Graduate Texts in Mathematics, 1996, New York, Springer-Verlag.10.1007/978-1-4612-0731-3Suche in Google Scholar

Received: 2018-04-18
Accepted: 2019-05-14
Published Online: 2019-07-31

© 2019 Yu and Pan, published by De Gruyter

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

Artikel in diesem Heft

  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
Heruntergeladen am 18.9.2025 von https://www.degruyterbrill.com/document/doi/10.1515/math-2019-0063/html
Button zum nach oben scrollen