English

Products of consecutive integers with unusual anatomy

Number Theory 2026-04-23 v2

Abstract

Call an interval {N+1,,N+H}\{N+1,\dots,N+H\} of consecutive natural numbers \emph{bad} if the product (N+1)(N+H)(N+1) \dots (N+H) is divisible by the square of its largest prime factor; \emph{very bad} if this product is powerful, and \emph{type F3F_3} if it has the same squarefree component as a factorial. Such concepts arose in the analysis of the factorial equation a1!a2!a3!=m2a_1! a_2! a_3! = m^2 with a1<a2<a3a_1<a_2<a_3. Answering several questions of Erd\H{o}s and Graham, we obtain asymptotics for the number of integers contained in bad or very bad intervals, and to get near-asymptotics for the number of right endpoints of a type F3F_3 interval, or on the number of solutions to a1!a2!a3!=m2a_1! a_2! a_3! = m^2.

Keywords

Cite

@article{arxiv.2603.27990,
  title  = {Products of consecutive integers with unusual anatomy},
  author = {Terence Tao},
  journal= {arXiv preprint arXiv:2603.27990},
  year   = {2026}
}

Comments

41 pages, 5 figures. More figures, expanded remarks