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 A358958 #5 Dec 08 2022 07:34:56
%S A358958 1,8,136,2720,60112,1414400,34744192,880722944,22866372480,
%T A358958 604987038208,16252230833792,442118711113216,12154717695451712,
%U A358958 337169716435693120,9425612400257630864,265272780558100130464,7510038750103097772890,213729057394800722424678,6110972702751703321123745
%N A358958 a(n) = coefficient of x^n in A(x) such that: 0 = Sum_{n=-oo..+oo} x^(8*n) * (x^n - 2*A(x))^(9*n+1).
%C A358958 Related identity: 0 = Sum_{n=-oo..+oo} x^n * (y - x^n)^n, which holds formally for all y.
%F A358958 G.f. A(x) = Sum_{n>=0} a(n)*x^n satisfies:
%F A358958 (1) 0 = Sum_{n=-oo..+oo} x^(8*n) * (x^n - 2*A(x))^(9*n+1).
%F A358958 (2) 0 = Sum_{n=-oo..+oo} x^(9*n*(n-1)) / (1 - 2*A(x)*x^n)^(9*n-1).
%e A358958 G.f.: A(x) = 1 + 8*x + 136*x^2 + 2720*x^3 + 60112*x^4 + 1414400*x^5 + 34744192*x^6 + 880722944*x^7 + 22866372480*x^8 + 604987038208*x^9 + 16252230833792*x^10 + ...
%o A358958 (PARI) {a(n) = my(A=[1]); for(i=1,n, A=concat(A,0);
%o A358958 A[#A] = polcoeff( sum(n=-#A,#A, x^(8*n) * (x^n - 2*Ser(A))^(9*n+1) ), #A-1)/2);A[n+1]}
%o A358958 for(n=0,25,print1(a(n),", "))
%Y A358958 Cf. A355865, A358952, A358953, A358954, A358955, A358956, A358957, A358959.
%K A358958 nonn
%O A358958 0,2
%A A358958 _Paul D. Hanna_, Dec 07 2022