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 A377555 #4 Nov 01 2024 07:14:16
%S A377555 1,1,3,25,121,861,10051,88453,972945,16663321,205667011,3069838641,
%T A377555 61038456073,997387656565,18623707785411,426663334715101,
%U A377555 8606752819074721,192052302116929713,5139946157328092035,122142504609497184841,3172736666738570349081,94751480557190553846541
%N A377555 E.g.f.: exp(Sum_{n>=1} A038500(n) * x^n).
%t A377555 nmax = 25; CoefficientList[Series[Exp[Sum[3^IntegerExponent[k, 3]*x^k, {k, 1, nmax}]], {x, 0, nmax}], x] * Range[0,nmax]!
%Y A377555 Cf. A038500, A161809, A377556.
%K A377555 nonn
%O A377555 0,3
%A A377555 _Vaclav Kotesovec_, Nov 01 2024