English

Well-Quasi-Order for Permutation Graphs Omitting a Path and a Clique

Combinatorics 2015-04-28 v2

Abstract

We consider well-quasi-order for classes of permutation graphs which omit both a path and a clique. Our principle result is that the class of permutation graphs omitting P5P_5 and a clique of any size is well-quasi-ordered. This is proved by giving a structural decomposition of the corresponding permutations. We also exhibit three infinite antichains to show that the classes of permutation graphs omitting {P6,K6}\{P_6,K_6\}, {P7,K5}\{P_7,K_5\}, and {P8,K4}\{P_8,K_4\} are not well-quasi-ordered.

Keywords

Cite

@article{arxiv.1312.5907,
  title  = {Well-Quasi-Order for Permutation Graphs Omitting a Path and a Clique},
  author = {Aistis Atminas and Robert Brignall and Nicholas Korpelainen and Vadim Lozin and Vincent Vatter},
  journal= {arXiv preprint arXiv:1312.5907},
  year   = {2015}
}

Comments

21 pages, 9 figures, to appear in Elec. J. Comb