A generalisation of Seymour's second neighbourhood conjecture

2020/01/20 by Jeck Lim, Lim, Jeck
Computer Science · Mathematics · #05C20 #Advanced Algebra and Logic #Advanced Combinatorial Mathematics #Advanced Graph Theory Research #Combinatorics (math.CO) #FOS: Mathematics

paper · pdf · doi:10.48550/arxiv.2001.07242

openalex publication_date 2020/01/20 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

In this note we propose a generalisation of Seymour's Second Neighbourhood Conjecture to two directed graphs on a vertex set. We prove that this generalisation holds in the case of tournaments, and we show that a natural strengthening of this conjecture does not hold.

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