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 A329967 #5 Nov 26 2019 20:06:03
%S A329967 1,1,0,-2,7,259,-28726,-21126778,106100219840,4280272610298752,
%T A329967 -1553116380131413822408,-5635994212344216419883091608,
%U A329967 224970666556043231138664445792724812,107761317610991666102026987955237496031475980
%N A329967 a(0) = 1; a(n) = Sum_{k=1..n} Stirling1(n,k) * a(n-k).
%t A329967 a[n_] := a[n] = Sum[StirlingS1[n, k] a[n - k], {k, 1, n}]; a[0] = 1; Table[a[n], {n, 0, 13}]
%Y A329967 Cf. A008275, A246040, A308444, A329968.
%K A329967 sign
%O A329967 0,4
%A A329967 _Ilya Gutkovskiy_, Nov 26 2019