English

Hamiltonicity of Schrijver graphs and stable Kneser graphs

Combinatorics 2024-06-03 v2 Discrete Mathematics

Abstract

For integers k1k\geq 1 and n2k+1n\geq 2k+1, the Schrijver graph S(n,k)S(n,k) has as vertices all kk-element subsets of [n]:={1,2,,n}[n]:=\{1,2,\ldots,n\} that contain no two cyclically adjacent elements, and an edge between any two disjoint sets. More generally, for integers k1k\geq 1, s2s\geq 2, and nsk+1n \geq sk+1, the ss-stable Kneser graph S(n,k,s)S(n,k,s) has as vertices all kk-element subsets of [n][n] in which any two elements are in cyclical distance at least ss. We prove that all the graphs S(n,k,s)S(n,k,s), in particular Schrijver graphs S(n,k)=S(n,k,2)S(n,k)=S(n,k,2), admit a Hamilton cycle that can be computed in time O(n)\mathcal{O}(n) per generated vertex.

Keywords

Cite

@article{arxiv.2401.01681,
  title  = {Hamiltonicity of Schrijver graphs and stable Kneser graphs},
  author = {Torsten Mütze and Namrata},
  journal= {arXiv preprint arXiv:2401.01681},
  year   = {2024}
}