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 A366431 #14 Oct 10 2023 05:11:31 %S A366431 1,1,5,25,135,775,4651,28845,183450,1190050,7844230,52389678, %T A366431 353770190,2411324700,16568343325,114639216915,798076174113, %U A366431 5586035989185,39287407321075,277508001643575,1967816928168265,14003018984540741,99965175670335750 %N A366431 G.f. A(x) satisfies A(x) = 1 + x * (A(x) / (1 - x))^(5/2). %F A366431 a(n) = Sum_{k=0..n} binomial(n+3*k/2-1,n-k) * binomial(5*k/2,k) / (3*k/2+1). %o A366431 (PARI) a(n) = sum(k=0, n, binomial(n+3*k/2-1, n-k)*binomial(5*k/2, k)/(3*k/2+1)); %Y A366431 Partial sums give A366400. %Y A366431 Cf. A006319, A071724, A213282, A213336, A366432, A366433, A366434, A366435, A366436, A366437. %K A366431 nonn %O A366431 0,3 %A A366431 _Seiichi Manyama_, Oct 09 2023