On two problems in Ramsey-Tur\'an theory
Abstract
Alon, Balogh, Keevash and Sudakov proved that the -partite Tur\'an graph maximizes the number of distinct -edge-colorings with no monochromatic for all fixed and , among all -vertex graphs. In this paper, we determine this function asymptotically for among -vertex graphs with sub-linear independence number. Somewhat surprisingly, unlike Alon-Balogh-Keevash-Sudakov's result, the extremal construction from Ramsey-Tur\'an theory, as a natural candidate, does not maximize the number of distinct edge-colorings with no monochromatic cliques among all graphs with sub-linear independence number, even in the 2-colored case. In the second problem, we determine the maximum number of triangles asymptotically in an -vertex -free graph with . The extremal graphs have similar structure to the extremal graphs for the classical Ramsey-Tur\'an problem, i.e.~when the number of edges is maximized.
Keywords
Cite
@article{arxiv.1607.06393,
title = {On two problems in Ramsey-Tur\'an theory},
author = {József Balogh and Hong Liu and Maryam Sharifzadeh},
journal= {arXiv preprint arXiv:1607.06393},
year = {2017}
}
Comments
22 pages