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 A161967 #2 Mar 30 2012 18:37:17 %S A161967 1,1,3,22,317,7596,270727,13332544,862740153,70762448080, %T A161967 7161344443691,875732817920544,127244974218410677, %U A161967 21666397760623131712,4273075677258426773295,966395699152796722817536 %N A161967 E.g.f. satisfies: A(x) = exp( x*exp( x*A'(x)/A(x) ) ), where A'(x)/A(x) = d/dx log(A(x)). %e A161967 E.g.f.: A(x) = 1 + x + 3*x^2/2! + 22*x^3/3! + 317*x^4/4! + 7596*x^5/5! +... %e A161967 A'(x)/A(x) = 1 + 2*x + 15*x^2/2! + 232*x^3/3! + 5905*x^4/4! + 220176*x^5/5! +... %e A161967 where x*exp( x*d/dx log(A(x)) ) = log(A(x)) = e.g.f. of A161968. %o A161967 (PARI) {a(n)=local(A=1+x);for(i=1,n,A=exp(x*exp(x*deriv(A)/(A+O(x^n)))));n!*polcoeff(A,n)} %Y A161967 Cf. A161968 (log). %K A161967 nonn %O A161967 0,3 %A A161967 _Paul D. Hanna_, Jun 23 2009