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 A229806 #16 Oct 02 2013 21:38:39 %S A229806 1,1,7,150,6924,569726,74358042,14229990742,3774315375580, %T A229806 1330122245198910,602741550311798067,342138788139339603446, %U A229806 238146938124253555981224,199695655908033678248780110,198741234873020798204357773510,231773141251670398730627959107510 %N A229806 G.f.: Sum_{n>=1} a(n)*x^n / (1 + n*x)^(n^2) = x. %C A229806 Compare to identity: Sum_{n>=1} n^(n-2) * x^n / (1 + n*x)^n = x. %e A229806 G.f.: x = 1*x/(1+x) + 1*x^2/(1+2*x)^4 + 7*x^3/(1+3*x)^9 + 150*x^4/(1+4*x)^16 + 6924*x^5/(1+5*x)^25 + 569726*x^6/(1+6*x)^36 +... %o A229806 (PARI) {a(n)=polcoeff(x-sum(k=1, n-1, a(k)*x^k/(1+k*x+x*O(x^n))^(k^2)), n)} %o A229806 for(n=1,20,print1(a(n),", ")) %Y A229806 Cf. A177447, A082157. %K A229806 nonn %O A229806 1,3 %A A229806 _Paul D. Hanna_, Oct 02 2013