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 A364864 #17 Dec 11 2024 05:36:34 %S A364864 1,1,2,4,6,-1,-58,-304,-1090,-2876,-4216,9244,106746,529962,1874628, %T A364864 4669760,4309742,-35179252,-277928680,-1269921008,-4214431912, %U A364864 -9197175241,30113526,128659598896,822227670866,3453484223084,10519017940952,18490932535144 %N A364864 G.f. A(x) satisfies A(x) = 1 + x*A(x)^3 / (1 + x*A(x)^3). %H A364864 Seiichi Manyama, <a href="/A364864/b364864.txt">Table of n, a(n) for n = 0..1000</a> %F A364864 a(n) = Sum_{k=0..n} (-1)^k * 2^(n-k) * binomial(n,k) * binomial(3*n+k+1,n) / (3*n+k+1). %F A364864 a(n) = (1/n) * Sum_{k=0..n-1} (-2)^k * binomial(n,k) * binomial(4*n-k,n-1-k) for n > 0. %F A364864 a(n) = (1/n) * Sum_{k=1..n} (-1)^(n-k) * binomial(n,k) * binomial(3*n,k-1) for n > 0. %o A364864 (PARI) a(n) = sum(k=0, n, (-1)^k*2^(n-k)*binomial(n, k)*binomial(3*n+k+1, n)/(3*n+k+1)); %Y A364864 Cf. A291534, A364865, A364866, A365218. %Y A364864 Cf. A001764, A271469, A363982, A364736, A378892. %Y A364864 Cf. A002293, A336538. %K A364864 sign %O A364864 0,3 %A A364864 _Seiichi Manyama_, Aug 11 2023