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 A111922 Numerator of x(n) = Sum_{k=1..n} ((odd part of k)/(k^5)). 5
 1, 33, 2705, 86641, 54233569, 18084523, 43438219723, 1390063548011, 337834614646673, 337850745678737, 4946795388123668417, 4946852336050088417, 141291773058735555757937, 141293528936024618797937 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Denominator of x(n) = A111923(n); x(n) = a(n)/A111923(n) -> (Pi^4)/93 = 30*zeta(4)/31. REFERENCES G. Pólya and G. Szegő, Problems and Theorems in Analysis II (Springer 1924, reprinted 1972), Part Eight, Chap. 1, Sect. 6, Problem 50. LINKS Eric Weisstein's World of Mathematics, Odd Part Eric Weisstein's World of Mathematics, Riemann Zeta Function EXAMPLE a(20) = 16405158877294964819100166210727563, A111923(20) = 15663005949803936428703787909120000: x(20) = a(20)/A111923(20) = 1.04738..., x(20)*31/30=1.08229.... CROSSREFS Cf. A000265, A013662, A111929, A111918, A111920, A111923. Sequence in context: A294954 A118641 A263908 * A136541 A263105 A284072 Adjacent sequences:  A111919 A111920 A111921 * A111923 A111924 A111925 KEYWORD nonn,frac AUTHOR Reinhard Zumkeller, Aug 21 2005 STATUS approved

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Last modified January 24 04:35 EST 2020. Contains 331183 sequences. (Running on oeis4.)