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 A359669 #7 Jan 18 2023 14:54:17
%S A359669 1,1,0,3,6,13,55,142,429,1495,4538,14894,50279,164189,554402,1883870,
%T A359669 6371434,21854442,75183191,259137380,899092908,3127293679,10907931688,
%U A359669 38188033950,133998312862,471339759941,1662075700667,5872497411731,20790187564837,73741279736768
%N A359669 a(n) = coefficient of x^n in A(x) where x = Sum_{n=-oo..+oo} (-1)^(n-1) * x^(n*(n+1)) * A(x)^(n^2).
%H A359669 Paul D. Hanna, <a href="/A359669/b359669.txt">Table of n, a(n) for n = 0..200</a>
%F A359669 G.f. A(x) = Sum_{n>=0} a(n)*x^n satisfies:
%F A359669 (1) x = Sum_{n=-oo..+oo} (-1)^(n-1) * x^(n*(n+1)) * A(x)^(n^2).
%F A359669 (2) -x = Product_{n>=1} (1 - x^(2*n)*A(x)^(2*n-1)) * (1 - x^(2*n-2)*A(x)^(2*n-1)) * (1 - x^(2*n)*A(x)^(2*n)), due to the Jacobi triple product identity.
%o A359669 (PARI) {a(n) = my(A=[1]); for(i=1, n, A = concat(A, 0);
%o A359669 A[#A] = polcoeff(x - sum(m=-#A, #A, (-1)^(m-1) * x^(m*(m+1)) * Ser(A)^(m^2) ), #A-1)); A[n+1]}
%o A359669 for(n=0, 30, print1(a(n), ", "))
%Y A359669 Cf. A359672.
%K A359669 nonn
%O A359669 0,4
%A A359669 _Paul D. Hanna_, Jan 17 2023