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 A384578 #12 Jun 04 2025 09:53:08 %S A384578 1,4,10,36,171,1032,7656,66144,651065,7170044,87058242,1152623008, %T A384578 16497960553,253521890800,4158356425944,72446946779420, %U A384578 1335030266607501,25927404824529616,528984983237731754,11306375975258492540,252529515598101796399,5880779189553142120704 %N A384578 G.f. A(x) satisfies A(x) = ( 1 + x * A(x*A(x))^(1/4) )^4. %F A384578 See A384582. %F A384578 G.f.: B(x)^4, where B(x) is the g.f. of A384574. %o A384578 (PARI) a(n, k=4) = if(k==0, 0^n, k*sum(j=0, n, binomial(4*n-4*j+k, j)/(4*n-4*j+k)*a(n-j, j))); %Y A384578 Column k=4 of A384582. %Y A384578 Cf. A384574. %K A384578 nonn %O A384578 0,2 %A A384578 _Seiichi Manyama_, Jun 04 2025