Startseite Solutions to problems about potentially Ks,t-bigraphic pair
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Solutions to problems about potentially Ks,t-bigraphic pair

  • Jian-Hua Yin EMAIL logo und Liang Zhang
Veröffentlicht/Copyright: 24. Juni 2022

Abstract

Let S = ( a 1 , , a m ; b 1 , , b n ) , where a 1 , , a m and b 1 , , b n are two nonincreasing sequences of nonnegative integers. The pair S = ( a 1 , , a m ; b 1 , , b n ) is said to be a bigraphic pair if there is a simple bipartite graph G = ( X Y , E ) such that a 1 , , a m and b 1 , , b n are the degrees of the vertices in X and Y , respectively. In this case, G is referred to as a realization of S . Given a bigraphic pair S , and a complete bipartite graph K s , t , we say that S is a potentially K s , t -bigraphic pair if some realization of S contains K s , t as a subgraph (with s vertices in the part of size m and t in the part of size n ). Ferrara et al. (Potentially H-bigraphic sequences, Discuss. Math. Graph Theory 29 (2009), 583–596) defined σ ( K s , t , m , n ) to be the minimum integer k such that every bigraphic pair S = ( a 1 , , a m ; b 1 , , b n ) with σ ( S ) = a 1 + + a m k is a potentially K s , t -bigraphic pair. This problem can be viewed as a “potential” degree sequence relaxation of the (forcible) Turán problem. Ferrara et al. determined σ ( K s , t , m , n ) for n m 9 s 4 t 4 . In this paper, we further determine σ ( K s , t , m , n ) for n m s and n + m 2 t 2 + t + s . As two corollaries, if n m t 2 + t + s 2 or if n m s and n 2 t 2 + t , the values σ ( K s , t , m , n ) are determined completely. These results give a solution to a problem due to Ferrara et al. and a solution to a problem due to Yin and Wang.

MSC 2010: 05C07; 05C35

1 Introduction

The study of vertex degrees in graphs has a long history, often asking when an n -tuple of nonnegative integers is realizable as the vertex degrees of a simple n -vertex graph with specified properties. Analogous problems are also studied for bipartite graphs. Let S = ( a 1 , , a m ; b 1 , , b n ) , where a 1 , , a m and b 1 , , b n are two sequences of nonnegative integers with a 1 a m and b 1 b n . We say that S is a bigraphic pair if there is a simple bipartite graph G with partite sets { x 1 , , x m } and { y 1 , , y n } such that the degree of x i is a i and the degree of y j is b j . In this case, we say that G is a realization of S . Two methods to determine if S is a bigraphic pair are the Gale-Ryser criteria [1,2] and the Havel-Hakimi-type algorithm [3].

Theorem 1.1

[1,2] S is a bigraphic pair if and only if i = 1 m a i = i = 1 n b i and i = 1 k a i i = 1 n min { k , b i } for k = 1 , , m (or i = 1 k b i i = 1 m min { k , a i } for k = 1 , , n ).

For 1 p m and 1 q n , let S ( a p ) = ( a 1 , , a p 1 , a p + 1 , , a m ; b 1 , , b n ) and S ( b q ) = ( a 1 , , a m ; b 1 , , b q 1 , b q + 1 , , b n ) , where b 1 b n is a rearrangement in nonincreasing order of b 1 1 , , b a p 1 , b a p + 1 , , b n and a 1 a m is a rearrangement in nonincreasing order of a 1 1 , , a b q 1 , a b q + 1 , , a m . We say that S ( a p ) (resp. S ( b q ) ) is the residual pair obtained from S by laying off a p (resp. b q ).

Theorem 1.2

[3] S is a bigraphic pair if and only if S ( a p ) (or S ( b q ) ) is a bigraphic pair.

We can also ask whether there is a realization satisfying a particular property. Let S = ( a 1 , , a m ; b 1 , , b n ) be a bigraphic pair, and let K s , t be the complete bipartite graph with partite sets of size s and t . We say that S is a potentially K s , t -bigraphic pair if some realization of S contains K s , t (with s vertices in the part of size m and t in the part of size n ). If some realization of S contains K s , t on those vertices having degree a 1 , , a s , b 1 , , b t , we say that S is a potentially A s , t -bigraphic pair. Ferrara et al. [4] proved that S is a potentially A s , t -bigraphic pair if and only if it is a potentially K s , t -bigraphic pair. Yin and Wang [5] developed a Havel-Hakimi-type algorithm to determine if S is a potentially K s , t -bigraphic pair. This algorithm can also be used to construct a graph with degree sequence pair S and containing K s , t on those vertices having degree a 1 , , a s , b 1 , , b t .

Let S = ( a 1 , , a m ; b 1 , , b n ) , where a 1 , , a m and b 1 , , b n are two nonincreasing sequences of nonnegative integers. Let 1 s m , 1 t n , a s t and b t s . We first define pairs S 0 , , S s as follows. Let S 0 = S . Let

S 1 = ( a 2 , , a m ; b 1 1 , , b t 1 , b t + 1 ( 1 ) , , b n ( 1 ) ) ,

where b t + 1 ( 1 ) b n ( 1 ) is a rearrangement in nonincreasing order of b t + 1 1 , , b a 1 1 , b a 1 + 1 , , b n . For 2 i s , given S i 1 = ( a i , , a m ; b 1 i + 1 , , b t i + 1 , b t + 1 ( i 1 ) , , b n ( i 1 ) ) , let

S i = ( a i + 1 , , a m ; b 1 i , , b t i , b t + 1 ( i ) , , b n ( i ) ) ,

where b t + 1 ( i ) b n ( i ) is a rearrangement in nonincreasing order of b t + 1 ( i 1 ) 1 , , b a i ( i 1 ) 1 , b a i + 1 ( i 1 ) , , b n ( i 1 ) .

We now define pairs S 0 , , S t as follows. Let S 0 = S . Let

S 1 = ( a 1 1 , , a s 1 , a s + 1 ( 1 ) , , a m ( 1 ) ; b 2 , , b n ) ,

where a s + 1 ( 1 ) a m ( 1 ) is a rearrangement in nonincreasing order of a s + 1 1 , , a b 1 1 , a b 1 + 1 , , a m . For 2 i t , given S i 1 = ( a 1 i + 1 , , a s i + 1 , a s + 1 ( i 1 ) , , a m ( i 1 ) ; b i , , b n ) , let

S i = ( a 1 i , , a s i , a s + 1 ( i ) , , a m ( i ) ; b i + 1 , , b n ) ,

where a s + 1 ( i ) a m ( i ) is a rearrangement in nonincreasing order of a s + 1 ( i 1 ) 1 , , a b i ( i 1 ) 1 , a b i + 1 ( i 1 ) , , a m ( i 1 ) .

Theorem 1.3

[5] S is a potentially A s , t -bigraphic pair if and only if S s (or S t ) is a bigraphic pair.

Motivated by the problem due to Erdős et al. [6] of finding the minimum integer k such that every realizable n -tuple with a sum of at least k is potentially K r -graphic, Ferrara et al. [4] investigated analogous problem for bipartite graphs. They defined σ ( K s , t , m , n ) to be the minimum integer k such that every bigraphic pair S = ( a 1 , , a m ; b 1 , , b n ) with σ ( S ) = a 1 + + a m k is a potentially K s , t -bigraphic pair. They determined σ ( K s , t , m , n ) when m and n are sufficiently large in terms of s and t . This problem can be viewed as a “potential” degree sequence relaxation of the (forcible) Turán problem.

Theorem 1.4

[4] If t s 1 and n m 9 s 4 t 4 , then σ ( K s , t , m , n ) = n ( s 1 ) + m ( t 1 ) ( t 1 ) ( s 1 ) + 1 .

Ferrara et al. proposed a problem as follows.

Problem 1.1

[4] This would be useful if one were interested in finding smaller bounds on the n and m necessary to assure Theorem 1.4.

Yin and Wang proved a new result as follows.

Theorem 1.5

[5] If t s 1 , n m s and n ( s + 1 ) t 2 ( 2 s 1 ) t + s 1 , then σ ( K s , t , m , n ) = n ( s 1 ) + m ( t 1 ) ( t 1 ) ( s 1 ) + 1 .

Yin and Wang also proposed a problem as follows.

Problem 1.2

[5] It would be meaningful to investigate a lower bound on n + m necessary to assure Theorem 1.5.

The purpose of this paper is to improve Theorem 1.5 and determine σ ( K s , t , m , n ) for n m s and n + m 2 t 2 + t + s , that is, a solution to Problems 1.2. As two corollaries, if n m t 2 + t + s 2 or if n m s and n 2 t 2 + t , the values σ ( K s , t , m , n ) are determined completely, that is, a solution to Problem 1.1.

Theorem 1.6

If t s 1 , n m s and n + m 2 t 2 + t + s , then σ ( K s , t , m , n ) = n ( s 1 ) + m ( t 1 ) ( t 1 ) ( s 1 ) + 1 .

Corollary 1.1

If t s 1 and n m t 2 + t + s 2 , then σ ( K s , t , m , n ) = n ( s 1 ) + m ( t 1 ) ( t 1 ) ( s 1 ) + 1 .

Corollary 1.2

If t s 1 , n m s and n 2 t 2 + t , then σ ( K s , t , m , n ) = n ( s 1 ) + m ( t 1 ) ( t 1 ) ( s 1 ) + 1 .

2 Proof of Theorem 1.6

In order to prove Theorem 1.6, we need some lemmas.

Lemma 2.1

[7] Theorem 1.1 remains valid if i = 1 k a i i = 1 n min { k , b i } is assumed only for those k for which a k > a k + 1 or k = m (or i = 1 k b i i = 1 m min { k , a i } is assumed only for those k for which b k > b k + 1 or k = n ).

Lemma 2.2

[5] Let S = ( a 1 , , a m ; b 1 , , b n ) be a bigraphic pair with a s t , b t s , m 1 b 1 b t = = b a 1 + 1 b a 1 + 2 b n and n 1 a 1 a s = = a b 1 + 1 a b 1 + 2 a m . For each S i = ( a i + 1 , , a m ; b 1 i , , b t i , b t + 1 ( i ) , , b n ( i ) ) with 0 i s , let t i = max { j b t + 1 ( i ) b t + j ( i ) 1 } . Then

  1. t s t s 1 t 0 a 1 + 1 t .

  2. For each i with 1 i s , we have b t + k ( i ) = b t + k ( i 1 ) for k > t i . Consequently, b t + k ( s ) = b t + k for k > t s .

Lemma 2.3

Let S = ( a 1 , , a m ; b 1 , , b n ) be a bigraphic pair with a s t , b t s , m 1 b 1 b t = = b a 1 + 1 b a 1 + 2 b n and n 1 a 1 a s = = a b 1 + 1 a b 1 + 2 a m . If i = 1 t ( b i b t ) + i = a s + 1 + 1 n b i t s , then S is a potentially A s , t -bigraphic pair.

Proof

It is trivial for s = 1 . Assume s 2 . By Theorem 1.3, we only need to check that S s = ( a s + 1 , , a m ; b 1 s , , b t s , b t + 1 ( s ) , , b n ( s ) ) is a bigraphic pair. Clearly, a s + 1 + + a m = ( b 1 s ) + + ( b t s ) + b t + 1 ( s ) + + b n ( s ) . Denote = b t and p = max { i a s + i = a s } . Then s + p b 1 + 1 , i.e., p b 1 + 1 s . By Lemma 2.1, it is enough to check that i = 1 k a s + i i = 1 t min { k , b i s } + i = t + 1 n min { k , b i ( s ) } for p k m s . Denote x = b t + 1 ( s ) . By b t + 1 ( s ) b t + 1 = , we have x . If k x , by k p b 1 + 1 s > b i s for 1 i t , then i = 1 t min { k , b i s } + i = t + 1 n min { k , b i ( s ) } = i = 1 t ( b i s ) + i = t + 1 n b i ( s ) = a s + 1 + + a m i = 1 k a s + i . Assume p k x 1 . If t s a s + 1 , by b a s + 1 + t b t + t s x 1 k , then i = 1 t min { k , b i s } + i = t + 1 n min { k , b i ( s ) } i = t + 1 a s + 1 + t min { k , b i ( s ) } = k a s + 1 i = 1 k a s + i . Assume t s < a s + 1 . Then by Lemma 2.2, b t + j ( s ) = b t + j for j a s + 1 . If k b a s + 1 + t , then i = 1 t min { k , b i s } + i = t + 1 n min { k , b i ( s ) } i = t + 1 a s + 1 + t min { k , b i ( s ) } = k a s + 1 i = 1 k a s + i . Assume k > b a s + 1 + t . For each i with a s + 1 + 1 i t + t s , we have min { k , b i ( s ) } = k = ( k ) b i ( k ) . Also, for each i with t + t s + 1 i a s + 1 + t , by Lemma 2.2, we have min { k , b i ( s ) } = min { k , b i } = min { ( k ) , b i } min { b i ( k ) , b i } = b i ( k ) . Therefore, i = 1 t min { k , b i s } + i = t + 1 n min { k , b i ( s ) } = i = 1 t ( b i s ) + i = t + 1 a s + 1 min { k , b i ( s ) } + i = a s + 1 + 1 a s + 1 + t min { k , b i ( s ) } + i = a s + 1 + t + 1 n min { k , b i ( s ) } i = 1 t ( ( b i ) + ( s ) ) + k ( a s + 1 t ) + i = a s + 1 + 1 a s + 1 + t ( b i ( k ) ) + i = a s + 1 + t + 1 n b i = i = 1 t ( b i ) + i = a s + 1 + 1 n b i + ( s ) t + k ( a s + 1 t ) ( k ) t t s + ( s ) t + k ( a s + 1 t ) ( k ) t = k a s + 1 i = 1 k a s + i .□

Lemma 2.4

Let S = ( a 1 , , a m ; b 1 , , b n ) be a bigraphic pair with a s t , b t s , m 1 b 1 b t = = b a 1 + 1 b a 1 + 2 b n and n 1 a 1 a s = = a b 1 + 1 a b 1 + 2 a m . If i = 1 s ( a i a s ) + i = b t + 1 + 1 m a i t s , then S is a potentially A s , t -bigraphic pair.

Proof

By the symmetry, the proof of Lemma 2.4 is similar to that of Lemma 2.3.□

Lemma 2.5

[4] Suppose that S = ( a 1 , , a m ; b 1 , , b n ) is not a potentially A s , t -bigraphic pair. Let G be a realization of S with partite sets X and Y , with X = m and Y = n . Let X s be the set of s highest degree vertices of X , and Y t be the set of t highest degree vertices of Y . Assume that G is a realization of S that maximizes the number of edges between X s and Y t . Let x and y be nonadjacent members of X s and Y t , and let A = N G ( x ) Y t and B = N G ( y ) X s . Then both A and B contain at most ( s 1 ) ( t 1 ) vertices.

Lemma 2.6

[7] If S = ( a 1 , , a m ; b 1 , , b n ) is a bigraphic pair with a s 2 t 1 and b t 2 s 1 , then S is a potentially A s , t -bigraphic pair.

Lemma 2.7

Let S = ( a 1 , , a m ; b 1 , , b n ) be a bigraphic pair with m 1 b 1 b t = = b a 1 + 1 b a 1 + 2 b n and n 1 a 1 a s = = a b 1 + 1 a b 1 + 2 a m . If n ( s 1 ) + m ( t 1 ) max { 2 s t 2 2 t 2 + t s , 2 t s 2 2 s 2 + s t } and σ ( S ) n ( s 1 ) + m ( t 1 ) ( t 1 ) ( s 1 ) + 1 , then S is a potentially A s , t -bigraphic pair.

Proof

By σ ( S ) n ( s 1 ) + m ( t 1 ) ( t 1 ) ( s 1 ) + 1 , it is straightforward to show that a s t and b t s . On the contrary, we assume that S is not a potentially A s , t -bigraphic pair. Let G be a realization of S with partite sets X and Y , with X = m and Y = n . Let X s be the set of s highest degree vertices of X , and Y t be the set of t highest degree vertices of Y . Assume that G is a realization of S that maximizes the number of edges between X s and Y t . Let x and y be nonadjacent members of X s and Y t , and let A = N G ( x ) Y t and B = N G ( y ) X s . By Lemma 2.5, both A and B contain at most ( s 1 ) ( t 1 ) vertices. This implies a s d G ( x ) A + Y t 1 ( s 1 ) ( t 1 ) + t 1 = s t s and b t d G ( y ) B + X s 1 ( s 1 ) ( t 1 ) + s 1 = s t t . By Lemma 2.6, we have a s 2 t 2 or b t 2 s 2 , and so we may consider the following two cases.

Case 1. a s 2 t 2 .

It follows from Lemma 2.3 that σ ( S ) = i = 1 t b i + i = t + 1 a s + 1 b i + i = a s + 1 + 1 n b i = i = 1 t ( b i b t + b t ) + i = t + 1 a s + 1 b i +  i = a s + 1 + 1 n b i i = 1 t ( b i b t ) + i = a s + 1 + 1 n b i  +  t b t + ( a s + 1 t ) b t t s 1 + a s + 1 b t t s 1 + ( 2 t 2 ) ( s t t ) < ( 2 s t 2 2 t 2 + t s ) ( t 1 ) ( s 1 ) + 1 n ( s 1 ) + m ( t 1 ) ( t 1 ) ( s 1 ) + 1 , a contradiction.

Case 2. b t 2 s 2 .

It follows from Lemma 2.4 that σ ( S ) = i = 1 s a i + i = s + 1 b t + 1 a i + i = b t + 1 + 1 m a i = i = 1 s ( a i a s + a s ) + i = s + 1 b t + 1 a i + i = b t + 1 + 1 m a i i = 1 s ( a i a s ) + i = b t + 1 + 1 m a i + s a s + ( b t + 1 s ) a s t s 1 + b t + 1 a s t s 1 + ( 2 s 2 ) ( s t s ) < ( 2 t s 2 2 s 2 + s t ) ( t 1 ) ( s 1 ) + 1 n ( s 1 ) + m ( t 1 ) ( t 1 ) ( s 1 ) + 1 , a contradiction.□

Lemma 2.8

Let S = ( a 1 , , a m ; b 1 , , b n ) be a bigraphic pair. If n + m 2 max { t 2 , s 2 } + t + s and σ ( S ) n ( s 1 ) + m ( t 1 ) ( t 1 ) ( s 1 ) + 1 , then S is a potentially A s , t -bigraphic pair.

Proof

It is straightforward to show that a s t and b t s . We use induction on s + t . It is trivial for s = 1 or t = 1 . Assume s 2 and t 2 . If a 1 = n or there exists an integer k with t k a 1 such that b k > b k + 1 , then the residual pair S ( a 1 ) = ( a 2 , , a m ; b 1 , , b n ) obtained from S by laying off a 1 satisfies n + ( m 1 ) 2 max { t 2 , s 2 } + t + ( s 1 ) 2 max { t 2 , ( s 1 ) 2 } + t + ( s 1 ) , σ ( S ( a 1 ) ) = σ ( S ) a 1 n ( s 1 ) + m ( t 1 ) ( t 1 ) ( s 1 ) + 1 n = n ( s 2 ) + ( m 1 ) ( t 1 ) ( t 1 ) ( s 2 ) + 1 and b 1 = b 1 1 , , b t = b t 1 . By Theorem 1.2 and the induction hypothesis, S ( a 1 ) is a potentially A s 1 , t -bigraphic pair, and hence S is a potentially A s , t -bigraphic pair. So we may assume a 1 n 1 and b 1 b t = = b a 1 + 1 b a 1 + 2 b n . If b 1 = m or there exists an integer k with s k b 1 such that a k > a k + 1 , then the residual pair S ( b 1 ) = ( a 1 , , a m ; b 2 , , b n ) obtained from S by laying off b 1 satisfies ( n 1 ) + m 2 max { t 2 , s 2 } + ( t 1 ) + s 2 max { ( t 1 ) 2 , s 2 } + ( t 1 ) + s , σ ( S ( b 1 ) ) = σ ( S ) b 1 n ( s 1 ) + m ( t 1 ) ( t 1 ) ( s 1 ) + 1 m = ( n 1 ) ( s 1 ) + m ( t 2 ) ( t 2 ) ( s 1 ) + 1 and a 1 = a 1 1 , , a s = a s 1 . By Theorem 1.2 and the induction hypothesis, S ( b 1 ) is a potentially A s , t 1 -bigraphic pair, and hence S is a potentially A s , t -bigraphic pair. So we may further assume b 1 m 1 and a 1 a s = = a b 1 + 1 a b 1 + 2 a m . If s t , then 2 s t 2 2 t 2 + t s 2 t s 2 2 s 2 + s t and n ( s 1 ) + m ( t 1 ) ( n + m ) ( s 1 ) ( 2 t 2 + t + s ) ( s 1 ) = 2 s t 2 2 t 2 + ( t + s ) ( s 1 ) 2 s t 2 2 t 2 + t + s , implying that n ( s 1 ) + m ( t 1 ) max { 2 s t 2 2 t 2 + t s , 2 t s 2 2 s 2 + s t } . Similarly, if t s , then 2 t s 2 2 s 2 + s t 2 s t 2 2 t 2 + t s and n ( s 1 ) + m ( t 1 ) ( n + m ) ( t 1 ) ( 2 s 2 + t + s ) ( t 1 ) = 2 t s 2 2 s 2 + ( t + s ) ( t 1 ) 2 t s 2 2 s 2 + t + s , implying that n ( s 1 ) + m ( t 1 ) max { 2 s t 2 2 t 2 + t s , 2 t s 2 2 s 2 + s t } . Thus by Lemma 2.7, S is a potentially A s , t -bigraphic pair.□

Proof of Theorem 1.6

To show the lower bound, Ferrara et al. [4] considered the bigraphic pair S = ( n s 1 , ( t 1 ) m s + 1 ; m s 1 , ( t 1 ) m s + 1 , ( s 1 ) n m ) , where the symbol x y stands for y consecutive terms, each equal to x . Clearly, neither partite set in any realization of S has s vertices of degree t . Hence, S is not a potentially K s , t -bigraphic pair. Thus, σ ( K s , t , m , n ) σ ( S ) + 1 = n ( s 1 ) + m ( t 1 ) ( t 1 ) ( s 1 ) + 1 . The upper bound directly follows from Lemma 2.8.□

Acknowledgements

The authors would like to thank the referees for their helpful suggestions.

  1. Funding information: This research was supported by Hainan Provincial Natural Science Foundation of China (Nos. 122RC545, 2019RC085), National Natural Science Foundation of China (No. 11961019), and Key Laboratory of Engineering Modeling and Statistical Computation of Hainan Province.

  2. Conflict of interest: The authors state no conflict of interest.

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Received: 2021-06-26
Accepted: 2022-01-12
Published Online: 2022-06-24

© 2022 Jian-Hua Yin and Liang Zhang, published by De Gruyter

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

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  58. Non-binary quantum codes from constacyclic codes over 𝔽q[u1, u2,…,uk]/⟨ui3 = ui, uiuj = ujui
  59. On the general position number of two classes of graphs
  60. A posteriori regularization method for the two-dimensional inverse heat conduction problem
  61. Orbital stability and Zhukovskiǐ quasi-stability in impulsive dynamical systems
  62. Approximations related to the complete p-elliptic integrals
  63. A note on commutators of strongly singular Calderón-Zygmund operators
  64. Generalized Munn rings
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  69. Hessian equations of Krylov type on compact Hermitian manifolds
  70. Class fields generated by coordinates of elliptic curves
  71. The lattice of (2, 1)-congruences on a left restriction semigroup
  72. A numerical solution of problem for essentially loaded differential equations with an integro-multipoint condition
  73. On stochastic accelerated gradient with convergence rate
  74. Displacement structure of the DMP inverse
  75. Dependence of eigenvalues of Sturm-Liouville problems on time scales with eigenparameter-dependent boundary conditions
  76. Existence of positive solutions of discrete third-order three-point BVP with sign-changing Green's function
  77. Some new fixed point theorems for nonexpansive-type mappings in geodesic spaces
  78. Generalized 4-connectivity of hierarchical star networks
  79. Spectra and reticulation of semihoops
  80. Stein-Weiss inequality for local mixed radial-angular Morrey spaces
  81. Eigenvalues of transition weight matrix for a family of weighted networks
  82. A modified Tikhonov regularization for unknown source in space fractional diffusion equation
  83. Modular forms of half-integral weight on Γ0(4) with few nonvanishing coefficients modulo
  84. Some estimates for commutators of bilinear pseudo-differential operators
  85. Extension of isometries in real Hilbert spaces
  86. Existence of positive periodic solutions for first-order nonlinear differential equations with multiple time-varying delays
  87. B-Fredholm elements in primitive C*-algebras
  88. Unique solvability for an inverse problem of a nonlinear parabolic PDE with nonlocal integral overdetermination condition
  89. An algebraic semigroup method for discovering maximal frequent itemsets
  90. Class-preserving Coleman automorphisms of some classes of finite groups
  91. Exponential stability of traveling waves for a nonlocal dispersal SIR model with delay
  92. Existence and multiplicity of solutions for second-order Dirichlet problems with nonlinear impulses
  93. The transitivity of primary conjugacy in regular ω-semigroups
  94. Stability estimation of some Markov controlled processes
  95. On nonnil-coherent modules and nonnil-Noetherian modules
  96. N-Tuples of weighted noncommutative Orlicz space and some geometrical properties
  97. The dimension-free estimate for the truncated maximal operator
  98. A human error risk priority number calculation methodology using fuzzy and TOPSIS grey
  99. Compact mappings and s-mappings at subsets
  100. The structural properties of the Gompertz-two-parameter-Lindley distribution and associated inference
  101. A monotone iteration for a nonlinear Euler-Bernoulli beam equation with indefinite weight and Neumann boundary conditions
  102. Delta waves of the isentropic relativistic Euler system coupled with an advection equation for Chaplygin gas
  103. Multiplicity and minimality of periodic solutions to fourth-order super-quadratic difference systems
  104. On the reciprocal sum of the fourth power of Fibonacci numbers
  105. Averaging principle for two-time-scale stochastic differential equations with correlated noise
  106. Phragmén-Lindelöf alternative results and structural stability for Brinkman fluid in porous media in a semi-infinite cylinder
  107. Study on r-truncated degenerate Stirling numbers of the second kind
  108. On 7-valent symmetric graphs of order 2pq and 11-valent symmetric graphs of order 4pq
  109. Some new characterizations of finite p-nilpotent groups
  110. A Billingsley type theorem for Bowen topological entropy of nonautonomous dynamical systems
  111. F4 and PSp (8, ℂ)-Higgs pairs understood as fixed points of the moduli space of E6-Higgs bundles over a compact Riemann surface
  112. On modules related to McCoy modules
  113. On generalized extragradient implicit method for systems of variational inequalities with constraints of variational inclusion and fixed point problems
  114. Solvability for a nonlocal dispersal model governed by time and space integrals
  115. Finite groups whose maximal subgroups of even order are MSN-groups
  116. Symmetric results of a Hénon-type elliptic system with coupled linear part
  117. On the connection between Sp-almost periodic functions defined on time scales and ℝ
  118. On a class of Harada rings
  119. On regular subgroup functors of finite groups
  120. Fast iterative solutions of Riccati and Lyapunov equations
  121. Weak measure expansivity of C2 dynamics
  122. Admissible congruences on type B semigroups
  123. Generalized fractional Hermite-Hadamard type inclusions for co-ordinated convex interval-valued functions
  124. Inverse eigenvalue problems for rank one perturbations of the Sturm-Liouville operator
  125. Data transmission mechanism of vehicle networking based on fuzzy comprehensive evaluation
  126. Dual uniformities in function spaces over uniform continuity
  127. Review Article
  128. On Hahn-Banach theorem and some of its applications
  129. Rapid Communication
  130. Discussion of foundation of mathematics and quantum theory
  131. Special Issue on Boundary Value Problems and their Applications on Biosciences and Engineering (Part II)
  132. A study of minimax shrinkage estimators dominating the James-Stein estimator under the balanced loss function
  133. Representations by degenerate Daehee polynomials
  134. Multilevel MC method for weak approximation of stochastic differential equation with the exact coupling scheme
  135. Multiple periodic solutions for discrete boundary value problem involving the mean curvature operator
  136. Special Issue on Evolution Equations, Theory and Applications (Part II)
  137. Coupled measure of noncompactness and functional integral equations
  138. Existence results for neutral evolution equations with nonlocal conditions and delay via fractional operator
  139. Global weak solution of 3D-NSE with exponential damping
  140. Special Issue on Fractional Problems with Variable-Order or Variable Exponents (Part I)
  141. Ground state solutions of nonlinear Schrödinger equations involving the fractional p-Laplacian and potential wells
  142. A class of p1(x, ⋅) & p2(x, ⋅)-fractional Kirchhoff-type problem with variable s(x, ⋅)-order and without the Ambrosetti-Rabinowitz condition in ℝN
  143. Jensen-type inequalities for m-convex functions
  144. Special Issue on Problems, Methods and Applications of Nonlinear Analysis (Part III)
  145. The influence of the noise on the exact solutions of a Kuramoto-Sivashinsky equation
  146. Basic inequalities for statistical submanifolds in Golden-like statistical manifolds
  147. Global existence and blow up of the solution for nonlinear Klein-Gordon equation with variable coefficient nonlinear source term
  148. Hopf bifurcation and Turing instability in a diffusive predator-prey model with hunting cooperation
  149. Efficient fixed-point iteration for generalized nonexpansive mappings and its stability in Banach spaces
Heruntergeladen am 5.11.2025 von https://www.degruyterbrill.com/document/doi/10.1515/math-2022-0022/html
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