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 A380041 #9 Jan 11 2025 10:27:49
%S A380041 1,1,6,67,1124,25325,718606,24629395,990296504,45718478137,
%T A380041 2383877762810,138578689119431,8887132981365508,623319005140469989,
%U A380041 47465740413056117894,3900149351529967753435,343951717449176947732976,32405206661688405897284849,3248370338004030319683766642
%N A380041 E.g.f. A(x) satisfies A(x) = 1/( 1 - 3*x*exp(x*A(x)^2) )^(1/3).
%F A380041 a(n) = n! * Sum_{k=0..n} 3^k * k^(n-k) * binomial(2*n/3+k/3+1/3,k)/( (2*n+k+1)*(n-k)! ).
%o A380041 (PARI) a(n) = n!*sum(k=0, n, 3^k*k^(n-k)*binomial(2*n/3+k/3+1/3, k)/((2*n+k+1)*(n-k)!));
%Y A380041 Cf. A380017, A380039.
%K A380041 nonn
%O A380041 0,3
%A A380041 _Seiichi Manyama_, Jan 10 2025