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 A356505 #6 Aug 10 2022 07:56:48
%S A356505 1,6,135,4284,160965,6684744,296679006,13805453160,665611197093,
%T A356505 32988925715610,1671463040525586,86231285273788180,
%U A356505 4516133521439246825,239551205985729110664,12846081444122599438850,695428535332816056597520,37960416340437631597631877
%N A356505 a(n) = A356500(2*n+1, 2*n) for n >= 0.
%C A356505 Triangle A356500 describes the coefficients in G(x,y) that satisfies: y = Sum_{n=-oo..+oo} (-x)^(n^2) * G(x,y)^((n-1)^2).
%o A356505 (PARI) {A356500(n,k) = my(A=[y],M); for(i=1,n, A = concat(A,0); M = ceil(sqrt(n+1));
%o A356505 A[#A] = -polcoeff( sum(m=-M,M, (-x)^(m^2)*Ser(A)^((m-1)^2)), #A-1)); polcoeff(A[n+1],k,y) }
%o A356505 for(n=0,20, print1( A356500(2*n+1, 2*n),", "))
%Y A356505 Cf. A356500, A356504, A356506.
%K A356505 nonn
%O A356505 0,2
%A A356505 _Paul D. Hanna_, Aug 09 2022