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a(n) = 1 + (1200 + (634 + (225 + (85 + (15 + n)*n)*n)*n)*n)*n/720.
6

%I #7 Nov 05 2024 20:15:09

%S 1,4,13,38,99,231,490,960,1761,3058,5071,8086,12467,18669,27252,38896,

%T 54417,74784,101137,134806,177331,230483,296286,377040,475345,594126,

%U 736659,906598,1108003,1345369,1623656,1948320,2325345,2761276,3263253,3839046,4497091

%N a(n) = 1 + (1200 + (634 + (225 + (85 + (15 + n)*n)*n)*n)*n)*n/720.

%H Alois P. Heinz, <a href="/A145128/b145128.txt">Table of n, a(n) for n = 0..1000</a>

%F G.f.: (x^4-4*x^3+6*x^2-3*x+1) / (1-x)^7.

%p a := n-> 1+ (1200+ (634+ (225+ (85+ (15+ n) *n) *n) *n) *n) *n/720: seq (a(n), n=0..40);

%Y 7th row of A145153. See row 7 of A145140/A145141 for rational coefficients and A145142 for 720 * coefficients of polynomial.

%K nonn,easy

%O 0,2

%A _Alois P. Heinz_, Oct 03 2008