A111923 Denominator of x(n) = Sum_{k=1..n} ((odd part of k)/(k^5)).

1, 32, 2592, 82944, 51840000, 17280000, 41489280000, 1327656960000, 322620641280000, 322620641280000, 4723488808980480000, 4723488808980480000, 134907563873291489280000, 134907563873291489280000

Offset

1,2

Comments

Numerator of x(n) = A111922(n);

lim_{n->infinity} x(n) = lim_{n->infinity} A111922(n)/a(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

Table of n, a(n) for n=1..14.

Eric Weisstein's World of Mathematics, Odd Part

Eric Weisstein's World of Mathematics, Riemann Zeta Function

Crossrefs

Cf. A000265, A013662, A111930, A111919, A111921, A111922.

Sequence in context: A077143 A198284 A230573 * A136246 A248074 A220299

Adjacent sequences: A111920 A111921 A111922 * A111924 A111925 A111926

Keyword

nonn,frac

Author

Reinhard Zumkeller, Aug 21 2005

Status

approved