On a conjecture of Szemer\'edi and Petruska
Abstract
Consider a -uniform hypergraph of order with clique number such that the intersection of all its -cliques is empty. Szemer\'edi and Petruska proved , for fixed , and they conjectured the sharp bound . Tuza proved the best known bound, , using the machinery of -critical hypergraphs. Here we propose an alternative approach, combining a decomposition process introduced by Szemer\'edi and Petruska with the skew version of Bollob\'as's theorem to prove . While the bound obtained here is weaker than Tuza's bound, it is a proof-of-concept for a different approach and a call to apply dimension bounds from linear algebra.
Keywords
Cite
@article{arxiv.1904.04921,
title = {On a conjecture of Szemer\'edi and Petruska},
author = {Adam S. Jobson and André E. Kézdy and Tim Pervenecki},
journal= {arXiv preprint arXiv:1904.04921},
year = {2019}
}
Comments
9 pages, no figures: Version 2 reflects new information about the best known upper bound. We are very grateful to Zsolt Tuza for alerting us to the best known upper bound, $\frac{3}{4}m^2+m+1$, for the maximum order of a $\tau$-critical $3$-uniform hypergraph with transversal number $m$