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 A111919 Denominator of x(n) = Sum((odd part of k)/(k^3): 1<=k<=n). 5
 1, 8, 72, 576, 14400, 1600, 78400, 627200, 50803200, 50803200, 6147187200, 6147187200, 1038874636800, 1038874636800, 1038874636800, 8310997094400, 2401878160281600, 266875351142400, 96342001762406400, 96342001762406400 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Numerator of x(n) = A111918(n); x(n) = A111918(n)/a(n) ---> Pi*Pi/7 = 6*zeta(2)/7. REFERENCES G. Polya and G. Szego, 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 zeta(2) CROSSREFS Cf. A000265, A013661, A111930, A111921, A111923. Sequence in context: A304826 A270241 A054615 * A052379 A246940 A158798 Adjacent sequences:  A111916 A111917 A111918 * A111920 A111921 A111922 KEYWORD nonn,frac AUTHOR Reinhard Zumkeller, Aug 21 2005 STATUS approved

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Last modified August 22 00:43 EDT 2019. Contains 326169 sequences. (Running on oeis4.)