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 A141004 #20 Aug 13 2025 10:18:59
%S A141004 1,4,28,258,2892,37778,560124,9256010,168182044,3325057826,
%T A141004 70934634236,1621828212826,39517131361884,1021237022557682,
%U A141004 27877344103738940,800976143703407210,24148078430008534428,761815206361252780098,25087729474993723079548
%N A141004 Expansion of e.g.f. exp(Sum_{d|6} (exp(d*x)-1)/d).
%H A141004 Vincenzo Librandi, <a href="/A141004/b141004.txt">Table of n, a(n) for n = 0..200</a>
%t A141004 u[0,j_]:=1;u[k_,j_]:=u[k,j]=Sum[Binomial[k-1,i-1]Plus@@(u[k-i,j]#^(i-1)&/@Divisors[j]),{i,k}]; Table[u[n,6],{n,0,18}] (* _Wouter Meeussen_, Dec 06 2008 *)
%Y A141004 u[n,j] generates for j=1, A000110 Bell numbers; j=2, A002872 "Sorting numbers"; j=3, A002874 "Sorting numbers"; j=4, A141003 (Mathar); j=5, A036075 "Sorting numbers"; j=6, A141004 (Mathar); j=7, A036077 "Sorting numbers". - _Wouter Meeussen_, Dec 06 2008
%Y A141004 Column k=6 of A162663.
%K A141004 nonn
%O A141004 0,2
%A A141004 _R. J. Mathar_, Jul 11 2008