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 A354553 #18 Aug 19 2022 02:25:25
%S A354553 1,1,1,1,25,121,361,3361,42001,275185,1819441,30777121,371238121,
%T A354553 3057311401,44263763545,801096528961,9710981323681,125367419194081,
%U A354553 2643123767954401,45840730383002305,646414025466298681,13258301279836276441
%N A354553 Expansion of e.g.f. exp( x * exp(x^3) ).
%H A354553 Seiichi Manyama, <a href="/A354553/b354553.txt">Table of n, a(n) for n = 0..475</a>
%F A354553 a(n) = n! * Sum_{k=0..floor(n/3)} (n - 3*k)^k/(k! * (n - 3*k)!).
%o A354553 (PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(exp(x*(exp(x^3)))))
%o A354553 (PARI) a(n) = n!*sum(k=0, n\3, (n-3*k)^k/(k!*(n-3*k)!));
%Y A354553 Cf. A000248, A216688, A354554.
%K A354553 nonn
%O A354553 0,5
%A A354553 _Seiichi Manyama_, Aug 18 2022