A195068 - OEIS

%I #5 Mar 30 2012 18:37:28

%S 1,1,2,7,37,279,2919,42011,833314,22937285,882905932,47833330376,

%T 3664667588132,398332024544864,61567508987316736,13553812089298857340,

%U 4254977588443309549759,1906584878492298737985244,1220249817955981418494900097

%N  G.f. satisfies: A(x) = Sum{n>=0} x^n * A(n*x)^n.

%e  G.f.: A(x) = 1 + x + 2*x^2 + 7*x^3 + 37*x^4 + 279*x^5 + 2919*x^6 +...

%e where:

%e A(x) = 1 + x*A(x) + x^2*A(2*x)^2 + x^3*A(3*x)^3 + x^4*A(4*x)^4 + x^5*A(5*x)^5 +...

%o  (PARI) {a(n)=local(A=1+x+x*O(x^n)); for(k=1, n, A=1+sum(j=1, n, x^j*subst(A,x,j*x)^j)); polcoeff(A, n)}

%K nonn

%O 0,3

%A _Paul D. Hanna_, Sep 08 2011