English

Hamilton cycles in random digraphs with minimum degree at least one

Combinatorics 2025-06-17 v2

Abstract

We study the existence of a directed Hamilton cycle in random digraphs with mm edges where we condition on minimum in- and out-degree at least one. Denote such a random graph by Dn,m(δ1)D_{n,m}^{(\delta\geq1)}. We prove that if m=n2(logn+2loglogn+cn)m=\tfrac n2(\log n+2\log\log n+c_n) then limnPr(Dn,m(δ1) is Hamiltonian)={0cn.eec/4cnc.1cn. \lim_{n\to\infty}\Pr(D_{n,m}^{(\delta\geq1)}\text{ is Hamiltonian})=\begin{cases}0&c_n\to-\infty.\\e^{-e^{-c}/4}&c_n\to c.\\1&c_n\to\infty.\end{cases}

Keywords

Cite

@article{arxiv.2312.06781,
  title  = {Hamilton cycles in random digraphs with minimum degree at least one},
  author = {Colin Cooper and Alan Frieze},
  journal= {arXiv preprint arXiv:2312.06781},
  year   = {2025}
}
R2 v1 2026-06-28T13:47:41.078Z