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 A317275 #6 Jul 25 2018 17:49:29
%S A317275 1,1,2,9,97,3105,409318,301069244,1523141657289,61447697339843710,
%T A317275 22299766257043761657829,80922067241038150103930448880,
%U A317275 3230152742688615187688660954252643194,1547248455508510864175770056662224501358437847
%N A317275 a(1) = 1; a(n) = Sum_{k=1..n-1} |Stirling1(n-1,k)|*a(k)*a(n-k).
%t A317275 a[n_] := a[n] = Sum[Abs[StirlingS1[n - 1, k]] a[k] a[n - k], {k, n - 1}]; a[1] = 1; Table[a[n], {n, 14}]
%Y A317275 Cf. A008275, A137731, A143805.
%K A317275 nonn
%O A317275 1,3
%A A317275 _Ilya Gutkovskiy_, Jul 25 2018