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 A090354 #9 May 28 2025 10:28:35
%S A090354 1,1,3,19,190,2574,43922,903986,21784659,601478195,18715354049,
%T A090354 647834803569,24688869993252,1027073272425876,46309250293477020,
%U A090354 2249435671825385244,117101538463333719891,6503918951175618656403
%N A090354 Self-convolution equals the binomial transform of A090353: A^2 = BINOMIAL(A090353).
%C A090354 See comments in A090353.
%H A090354 Vaclav Kotesovec, <a href="/A090354/b090354.txt">Table of n, a(n) for n = 0..370</a>
%F A090354 a(n) ~ (n-1)! / (18 * log(4/3)^(n+1)). - _Vaclav Kotesovec_, May 28 2025
%o A090354 (PARI) {a(n)=local(A); if(n<1,0,A=1+x+x*O(x^n); for(k=1,n,B=subst(A^3,x, x/(1-x))/(1-x)+x*O(x^n); A=A-A^4+B);B=subst(A,x, x/(1-x))/(1-x)+x*O(x^n); polcoeff(B^(1/2),n,x))}
%Y A090354 Cf. A090353, A090355.
%K A090354 nonn
%O A090354 0,3
%A A090354 _Paul D. Hanna_, Nov 26 2003