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 A371582 #18 Mar 29 2024 15:21:26
%S A371582 1,2,15,146,1623,19526,247516,3256118,44037023,608484766,8552832116,
%T A371582 121908218724,1757915510695,25598937436696,375916184707142,
%U A371582 5560517754432772,82774606577536376,1239110145377709862,18641533742708676711,281697878640036748684
%N A371582 G.f. satisfies A(x) = ( 1 + x*A(x)^3 / (1 - x*A(x)) )^2.
%F A371582 If g.f. satisfies A(x) = ( 1 + x*A(x)^(t/r) / (1 - x*A(x)^(u/r))^s )^r, then a(n) = r * Sum_{k=0..n} binomial(t*k+u*(n-k)+r,k) * binomial(n+(s-1)*k-1,n-k)/(t*k+u*(n-k)+r).
%o A371582 (PARI) a(n, r=2, s=1, t=6, u=2) = r*sum(k=0, n, binomial(t*k+u*(n-k)+r, k)*binomial(n+(s-1)*k-1, n-k)/(t*k+u*(n-k)+r));
%Y A371582 Cf. A006013, A211789, A365146, A371581.
%Y A371582 Cf. A371575.
%K A371582 nonn
%O A371582 0,2
%A A371582 _Seiichi Manyama_, Mar 28 2024