%I #8 Mar 26 2018 20:21:39
%S 1,3,7,17,39,89,203,459,1029,2299,5129,11409,25273,55787,122875,
%T 270239,593331,1299883,2841243,6197855,13499235,29366411,63809311,
%U 138466835,300036895,649186659,1402796793,3027908077,6529611587,14068804905
%N A007318 * A157019.
%C Equals row sums of triangle A157028.
%F G.f.: Sum_{n>=1} x^n * (1-x)^(n*(n-1)) / ((1-x)^n - x^n)^n. - _Paul D. Hanna_, Mar 26 2018
%F G.f.: Sum_{n>=1} x^n/(1-x)^n / (1 - x^n/(1-x)^n)^n. - _Paul D. Hanna_, Mar 26 2018
%e a(4) = 17 = (1, 3, 3, 1) dot (1, 2, 2, 4) = (1 + 6 + 6 + 4). a(4) = 17 = sum of row 4 terms, triangle A157028: (8 + 5 + 3 + 1).
%e G.f.: A(x) = x + 3*x^2 + 7*x^3 + 17*x^4 + 39*x^5 + 89*x^6 + 203*x^7 + 459*x^8 + 1029*x^9 + 2299*x^10 + ...
%e such that
%e A(x) = x/((1-x) - x) + x^2*(1-x)^2/((1-x)^2 - x^2)^2 + x^3*(1-x)^6/((1-x)^3 - x^3)^3 + x^4*(1-x)^12/((1-x)^4 - x^4)^4 + x^5*(1-x)^20/((1-x)^5 - x^5)^5 + ...
%Y Cf. A157019, A157028, A156348
%K nonn
%O 1,2
%A _Gary W. Adamson_ & _Mats Granvik_, Feb 21 2009
%E Extended by _R. J. Mathar_, Apr 07 2009