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Denominators of partial sums for a series for (Pi^4)/96.
4

%I #5 Dec 05 2013 10:26:32

%S 1,81,50625,121550625,9845600625,144149438750625,4117052120156600625,

%T 4117052120156600625,343860310127599440800625,

%U 44812219476138886724578250625,44812219476138886724578250625

%N Denominators of partial sums for a series for (Pi^4)/96.

%C Numerators are given in A120269.

%C See the comments and the W. Lang link under A120269.

%F a(n)=denominator(r(n)) with r(n):=sum(1/(2*k-1)^4,k=1..n).

%t a[n_] := (Pi^4 - PolyGamma[3, n + 1/2])/96 // Simplify // Denominator; Table[a[n], {n, 1, 11}] (* _Jean-François Alcover_, Dec 05 2013 *)

%K nonn,frac,easy

%O 1,2

%A _Wolfdieter Lang_ Apr 04 2007