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%I #5 Mar 30 2012 18:37:33
%S 1,1,13,2299,4465027,83649932869,14413888012788031,
%T 22412828378864422506133,312169717565869706933620630009,
%U 38865154523992131836783382601539858727,43266472789023671032936589458127528396392744933
%N G.f.: exp( Sum_{n>=1} (3^n - 2^n)^n * x^n/n ).
%C More generally, for integers p and q, exp( Sum_{n>=1} (p^n - q^n)^n * x^n/n ) is a power series in x with integer coefficients.
%e G.f.: A(x) = 1 + x + 13*x^2 + 2299*x^3 + 4465027*x^4 + 83649932869*x^5 +...
%e where
%e log(A(x)) = (3-2)*x + (3^2 - 2^2)^2*x^2/2 + (3^3 - 2^3)^3*x^3/3 + (3^4 - 2^4)^4*x^4/4 + (3^5 - 2^5)^5*x^5/5 +...
%e more explicitly,
%e log(A(x)) = x + 5^2*x^2/2 + 19^3*x^3/3 + 65^4*x^4/4 + 211^5*x^5/5 +...
%o (PARI) {a(n)=polcoeff(exp(sum(m=1,n,(3^m-2^m)^m*x^m/m)+x*O(x^n)),n)}
%Y Cf. A202516, A155200, A155201, A155202.
%K nonn
%O 0,3
%A _Paul D. Hanna_, Dec 20 2011
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