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 A126443 #23 Jun 18 2022 11:30:54
%S A126443 1,1,3,17,179,3489,127459,8873137,1195313043,315321098561,
%T A126443 164239990789571,169810102632595281,349630019758589841523,
%U A126443 1436268949679165936016097,11784559509424676876673518499,193243076262167105764611875139569
%N A126443 a(n) = Sum_{k=0..n-1} C(n-1,k)*a(k)*2^k for n>0, with a(0)=1.
%C A126443 Generated by a generalization of a recurrence for the Bell numbers (A000110).
%C A126443 Starting with offset 1 = eigensequence of triangle A013609. - _Gary W. Adamson_, Sep 04 2009
%H A126443 Seiichi Manyama, <a href="/A126443/b126443.txt">Table of n, a(n) for n = 0..81</a>
%F A126443 a(n) = Sum_{k=0..n*(n-1)/2} A126347(n,k)*2^k.
%F A126443 G.f. A(x) satisfies: A(x) = 1 + x*A(2*x/(1 - x))/(1 - x). - _Ilya Gutkovskiy_, Sep 02 2019
%F A126443 a(n) ~ c * 2^(n*(n-1)/2), where c = A081845 = 4.7684620580627434482997985... - _Vaclav Kotesovec_, Sep 16 2019
%o A126443 (PARI) a(n)=if(n==0,1,sum(k=0,n-1,binomial(n-1,k)*a(k)*2^k))
%Y A126443 Cf. A126347, A000110.
%Y A126443 Cf. A013609. - _Gary W. Adamson_, Sep 04 2009
%Y A126443 Column k=2 of A306245.
%K A126443 nonn
%O A126443 0,3
%A A126443 _Paul D. Hanna_, Jan 01 2007