This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A261779 #10 Nov 17 2019 01:43:17
%S A261779 1,1,1,2,5,20,103,630,4480,36288,329891,3326400,36846277,444787200,
%T A261779 5811886080,81729648000,1230752346353,19760412672000,336967037143579,
%U A261779 6082255020441600,115852476579840000,2322315553259520000,48869596859895986087,1077167364120207360000,24817936069329577574400,596585001666576384000000
%N A261779 a(n) = ceiling((n-1)! / n).
%C A261779 Except for n = 4, this is ((n-1)!+1)/n for prime n, and (n-1)!/n otherwise.
%t A261779 Table[Ceiling[((n-1)!)/n],{n,30}] (* _Harvey P. Dale_, Oct 04 2018 *)
%o A261779 (PARI) a(n) = ceil((n-1)!/n)
%Y A261779 Cf. A007619 (prime index elements).
%K A261779 nonn
%O A261779 1,4
%A A261779 _Franklin T. Adams-Watters_, Aug 31 2015