English

Uniform Convergence of an Asymptotic Approximation to Associated Stirling Numbers

Combinatorics 2024-09-04 v1

Abstract

Let Sr(p,q)S_r(p,q) be the rr-associated Stirling numbers of the second kind, the number of ways to partition a set of size pp into qq subsets of size at least rr. For r=1r=1, these are the standard Stirling numbers of the second kind, and for r=2r=2, these are also known as the Ward Numbers. This paper concerns asymptotic expansions of these Stirling numbers; such expansions have been known for many years. However, while uniform convergence of these expansions was conjectured in Hennecart's 1994 paper, it has not been fully proved. A recent paper (Connamacher and Dobrosotskaya, 2020) went a long way, by proving uniform convergence on a large set. In this paper we build on that paper and prove convergence "everywhere."

Keywords

Cite

@article{arxiv.2409.01489,
  title  = {Uniform Convergence of an Asymptotic Approximation to Associated Stirling Numbers},
  author = {E. Rodney Canfield and J. William Helton and Jared A. Hughes},
  journal= {arXiv preprint arXiv:2409.01489},
  year   = {2024}
}

Comments

15 pages, 2 figures