New values for the bipartite Ramsey number of the four-cycle versus stars

Sam Mattheus, Tamás Héger, Imre Hatala

Research output: Contribution to journalArticle

18 Downloads (Pure)

Abstract

We provide new values of the bipartite Ramsey number RB(C4,K1,n) using induced subgraphs of the incidence graph of a projective plane. The approach, based on deleting subplanes of projective planes, has been used in related extremal problems and allows us to unify previous results and extend them. More importantly, using deep stability results on 2modp sets and double blocking sets, we can show some of the limits of this technique when the projective plane is Desarguesian of large enough square order. Finally, we also disprove two conjectures about RB(C4,K1,n).

Original languageEnglish
Article number112320
Number of pages14
JournalDiscrete Mathematics
Volume344
Issue number5
DOIs
Publication statusPublished - May 2021

Fingerprint Dive into the research topics of 'New values for the bipartite Ramsey number of the four-cycle versus stars'. Together they form a unique fingerprint.

Cite this