About the second neighborhood conjecture for tournaments missing two stars or disjoint paths

M Daamouch, S Ghazal, D Al-Mniny - arXiv preprint arXiv:2406.03635, 2024 - arxiv.org
Seymour's Second Neighborhood Conjecture (SSNC) asserts that every oriented finite
simple graph (without digons) has a vertex whose second out-neighborhood is at least as …

[HTML][HTML] Seymour's second neighborhood conjecture for 5-anti-transitive oriented graphs

M Daamouch - Discrete Applied Mathematics, 2020 - Elsevier
Abstract k≥ 2 be an integer. A digraph D=(V, E) is k-anti-transitive if for every pair of vertices
u, v∈ V, the existence of a directed path of length k from u to v implies that (u, v)∉ E. Under …

[PDF][PDF] Seymour's second neighborhood conjecture for some oriented graphs with no sink

M Daamouch - Discrete Mathematics Letters, 2020 - researchgate.net
Abstract Seymour's Second Neighborhood Conjecture (SNC) asserts that every oriented
graph has a vertex whose second out-neighborhood is at least as large as its first out …

A note on Seymour's second neighborhood conjecture

B Chen, A Chang - Discrete Applied Mathematics, 2023 - Elsevier
Abstract Seymour's Second Neighborhood Conjecture (SSNC) asserts that there always
exists a vertex v such that the cardinality of its second out-neighborhood is at least as large …

Seymour's second neighborhood conjecture for 6-antitransitive digraphs

ZR Hassan, IF Khan, MI Poshni, M Shabbir - Discrete Applied Mathematics, 2021 - Elsevier
Abstract Seymour's Second Neighborhood Conjecture states that every simple oriented
graph has a vertex such that the cardinality of its second neighborhood is greater than or …

Strong -transitive oriented graphs with large minimum degree

M Daamouch - Communications in Combinatorics and …, 2025 - comb-opt.azaruniv.ac.ir
A digraph $ D=(V, E) $ is $ k $-transitive if for any directed $ uv $-path of length $ k $, we
have $(u, v)\in E $. In this paper, we study the structure of strong $ k $-transitive oriented …

Critical Kernel Imperfectness in -quasi-transitive and -anti-transitive digraphs of small diameter

G Benítez-Bobadilla, H Galeana-Sánchez… - arXiv preprint arXiv …, 2024 - arxiv.org
A kernel in a digraph is an independent and absorbent subset of its vertex set. A digraph is
critical kernel imperfect if it does not have a kernel, but every proper induced subdigraph …

A note on the second neighborhood problem for -anti-transitive and -free digraphs

D Mezher, M Daamouch - arXiv preprint arXiv:2405.17797, 2024 - arxiv.org
Seymour Second Neighborhood Conjecture (SSNC) asserts that every finite oriented graph
has a vertex whose second out-neighborhood is at least as large as its first out …

Seymour's Second Neighborhood Conjecture for m‐Free Oriented Graphs

H Ma - Mathematical Problems in Engineering, 2022 - Wiley Online Library
Let (D=(V, E)) be an oriented graph with minimum out‐degree δ+. For x∈ V (D), let d D+ x
and d D++ x be the out‐degree and second out‐degree of x in D, respectively. For a directed …

Digraphs each of whose vertices has its outdegree and second outdegree equal

이호준 - 2022 - s-space.snu.ac.kr
Seymour's Second Neighborhood Conjecture asserts that every digraph has a vertex $ v $
whose second out-neighborhood $ N^{++}(v) $ is at least as large as its out-neighborhood …