Triangles in graphs without bipartite suspensions
Abstract
Given graphs and , the generalized Tur\'an number ex is the maximum number of copies of in an -vertex graph with no copies of . Alon and Shikhelman, using a result of Erd\H os, determined the asymptotics of ex when the chromatic number of is greater than 3 and proved several results when is bipartite. We consider this problem when has chromatic number 3. Even this special case for the following relatively simple 3-chromatic graphs appears to be challenging. The suspension of a graph is the graph obtained from by adding a new vertex adjacent to all vertices of . We give new upper and lower bounds on ex when is a path, even cycle, or complete bipartite graph. One of the main tools we use is the triangle removal lemma, but it is unclear if much stronger statements can be proved without using the removal lemma.
Keywords
Cite
@article{arxiv.2004.11930,
title = {Triangles in graphs without bipartite suspensions},
author = {Dhruv Mubayi and Sayan Mukherjee},
journal= {arXiv preprint arXiv:2004.11930},
year = {2023}
}
Comments
New result about path with 5 edges added, Journal ref added