Seymour's Second Neighborhood Conjecture for orientations of (pseudo)random graphs

Seymour's Second Neighborhood Conjecture (SNC) states that every oriented graph contains a vertex whose second neighborhood is as large as its first neighborhood. We investigate the SNC for orientations of both binomial and pseudo random graphs, verifying the SNC asymptotically almost surely (a...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:Discrete mathematics 2023-12, Vol.346 (12), p.113583, Article 113583
Hauptverfasser: Botler, Fábio, Moura, Phablo F.S., Naia, Tássio
Format: Artikel
Sprache:eng
Schlagworte:
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:Seymour's Second Neighborhood Conjecture (SNC) states that every oriented graph contains a vertex whose second neighborhood is as large as its first neighborhood. We investigate the SNC for orientations of both binomial and pseudo random graphs, verifying the SNC asymptotically almost surely (a.a.s.)1.for all orientations of G(n,p) if limsupn→∞p0 is a universal constant independent of both n and p. We also show that a.a.s. the SNC holds for almost every orientation of G(n,p). More specifically, we prove that a.a.s.1.for all ε>0 and p=p(n) with limsupn→∞p≤2/3−ε, every orientation of G(n,p) with minimum outdegree Ωε(n) satisfies the SNC; and2.for all p=p(n), a random orientation of G(n,p) satisfies the SNC. We remark that either (iii) or (iv) confirms the SNC for almost every oriented graph.
ISSN:0012-365X
DOI:10.1016/j.disc.2023.113583