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%I #2 Mar 30 2012 18:37:11
%S 1,1,4,23,175,1678,19579,270683,4342447,79498622,1638471038,
%T 37592670383,951214496814,26333793485772,792232525678756,
%U 25747819699179668,899388184082559576,33613386298645020835,1338749843351681925409
%N Column 3 of triangle A141760.
%F G.f.: 1/(1-x) = Sum_{n>=0} a(n) * x^n/(1+x)^{(n+2)*(n+3)/2 - 3}.
%F a(n) = 1 - Sum_{j=0..n-1} a(j) * (-1)^(n-j) * C((j+2)(j+3)/2 + n-j-4, n-j) for n>0, with a(0)=1.
%o (PARI) {a(n)=if(n==0,1,1 - sum(j=0,n-1,a(j)*(-1)^(n-j)*binomial((j+2)*(j+3)/2-3+n-j-1,n-j)))}
%Y Cf. A141760, A141761, A141762, A141764.
%K nonn
%O 0,3
%A _Paul D. Hanna_, Jul 18 2008
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