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A126463 Column 3 of triangle A126460; equals the number of subpartitions of the partition {(k^2 + 9*k + 20)*k/6, k>=0}. 4

%I #3 Mar 30 2012 18:37:02

%S 1,1,10,195,5940,257300,14989472,1130000385,107089958760,

%T 12470885416545,1751753684302150,292264756622072214,

%U 57165584968923450000,12962148519535236156640,3374220800446022166695530

%N Column 3 of triangle A126460; equals the number of subpartitions of the partition {(k^2 + 9*k + 20)*k/6, k>=0}.

%F G.f.: 1/(1-x) = Sum_{k>=0} a(k)*x^k*(1-x)^[(k^2 + 12*k + 41)*k/6].

%e Equals the number of subpartitions of the partition:

%e {(k^2 + 12*k + 41)*k/6, k>=0} = [0,9,23,43,70,105,149,203,268,345,...]

%e as illustrated by g.f.:

%e 1/(1-x) = 1*(1-x)^0 + 1*x*(1-x)^9 + 10*x^2*(1-x)^23 + 195*x^3*(1-x)^43 + 5940*x^4*(1-x)^70 + 257300*x^5*(1-x)^105 + 14989472*x^6*(1-x)^149 + 1130000385*x^7*(1-x)^203 ...

%o (PARI) {a(n)=polcoeff(1-sum(k=0, n-1, a(k)*x^k*(1-x+x*O(x^n))^(1+(k^2+12*k+41)*k/6)),n)}

%Y Cf. A126460; A126461, A126462, A126464.

%K nonn

%O 0,3

%A _Paul D. Hanna_, Dec 27 2006

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Last modified March 29 08:13 EDT 2024. Contains 371265 sequences. (Running on oeis4.)