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 A128493 Denominators of partial sums for a series for (Pi^4)/96. 4
 1, 81, 50625, 121550625, 9845600625, 144149438750625, 4117052120156600625, 4117052120156600625, 343860310127599440800625, 44812219476138886724578250625, 44812219476138886724578250625 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Numerators are given in A120269. See the comments and the W. Lang link under A120269. LINKS FORMULA a(n)=denominator(r(n)) with r(n):=sum(1/(2*k-1)^4,k=1..n). MATHEMATICA a[n_] := (Pi^4 - PolyGamma[3, n + 1/2])/96 // Simplify // Denominator; Table[a[n], {n, 1, 11}] (* Jean-François Alcover, Dec 05 2013 *) CROSSREFS Sequence in context: A189149 A088188 A017560 * A145261 A013745 A093227 Adjacent sequences:  A128490 A128491 A128492 * A128494 A128495 A128496 KEYWORD nonn,frac,easy AUTHOR Wolfdieter Lang Apr 04 2007 STATUS approved

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Last modified April 8 14:52 EDT 2020. Contains 333314 sequences. (Running on oeis4.)