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 A384145 #21 Jun 06 2025 08:36:01 %S A384145 1,1,2,8,44,298,2359,21112,209175,2262121,26431042,331096188, %T A384145 4419824468,62565545535,935341395343,14716294925179,242945752432294, %U A384145 4197094127399756,75698807290515322,1422350601250404765,27788515730656558613,563512508612712699574,11841983002490204813514 %N A384145 G.f. A(x) satisfies A(x) = 1/( 1 - x*A(x*A(x)^3) ). %F A384145 See A384652. %o A384145 (PARI) a(n, k=1) = if(k==0, 0^n, k*sum(j=0, n, binomial(3*n-2*j+k, j)/(3*n-2*j+k)*a(n-j, j))); %Y A384145 Column k=1 of A384652. %Y A384145 Cf. A110447, A162661, A384649, A384650. %K A384145 nonn %O A384145 0,3 %A A384145 _Seiichi Manyama_, Jun 06 2025