Unavoidable Induced Subgraphs of Large 2-Connected Graphs
arXiv:2009.12503 · doi:10.1137/21M1447593
Abstract
Ramsey proved that for every positive integer , every sufficiently large graph contains an induced or . Among the many extensions of Ramsey's Theorem there is an analogue for connected graphs: for every positive integer , every sufficiently large connected graph contains an induced , , or . In this paper, we establish an analogue for 2-connected graphs. In particular, we prove that for every integer exceeding two, every sufficiently large 2-connected graph contains one of the following as an induced subgraph: , a subdivision of , a subdivision of with an edge between the two vertices of degree , and a well-defined structure similar to a ladder.
15 pages