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 A357965 #8 Oct 22 2022 14:02:18 %S A357965 1,1,1,1,1,61,361,1261,3361,68041,1073521,8343721,43290721,432509221, %T A357965 11472541081,165124339381,1457296102081,12237047593681, %U A357965 322364521392481,7462073325643921,103362225413048641,1051987428484484941,21127644716862970441 %N A357965 Expansion of e.g.f. exp( (exp(x^4) - 1)/x^3 ). %F A357965 a(n) = n! * Sum_{k=0..floor(n/4)} Stirling2(n-3*k,n-4*k)/(n-3*k)!. %o A357965 (PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(exp((exp(x^4)-1)/x^3))) %o A357965 (PARI) a(n) = n!*sum(k=0, n\4, stirling(n-3*k, n-4*k, 2)/(n-3*k)!); %Y A357965 Cf. A357962, A357964. %Y A357965 Cf. A353225. %K A357965 nonn %O A357965 0,6 %A A357965 _Seiichi Manyama_, Oct 22 2022