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 A081624 #11 May 11 2016 10:24:25 %S A081624 1,1,8,92,1380,25488,558426,14140722,406005804,13024655442, %T A081624 461451524934,17886290630832,752602671853068,34152212772528222, %U A081624 1662095923363838817,86335146917372644026,4766427291743224251474,278658370977555551901990 %N A081624 Number of 8-level labeled rooted trees with n leaves. %D A081624 J. Ginsburg, Iterated exponentials, Scripta Math., 11 (1945), 340-353. %D A081624 T. Hogg and B. A. Huberman, Attractors on finite sets: the dissipative dynamics of computing structures, Phys. Review A 32 (1985), 2338-2346. %H A081624 Alois P. Heinz, <a href="/A081624/b081624.txt">Table of n, a(n) for n = 0..150</a> %F A081624 E.g.f.: exp(exp(exp(exp(exp(exp(exp(exp(x)-1)-1)-1)-1)-1)-1)-1). %o A081624 (PARI) a(n)=local(X); if(n<0,0,X=x+x*O(x^n); n!*polcoeff(exp(exp(exp(exp(exp(exp(exp(exp(X)-1)-1)-1)-1)-1)-1)-1),n)) %Y A081624 Cf. A000110, A000258, A000307, A000357, A001669. %Y A081624 Column k=7 of A144150. %K A081624 nonn %O A081624 0,3 %A A081624 _Benoit Cloitre_, Apr 23 2003