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A111922 Numerator of x(n) = Sum((odd part of k)/(k^5): 1<=k<=n). 5
1, 33, 2705, 86641, 54233569, 18084523, 43438219723, 1390063548011, 337834614646673, 337850745678737, 4946795388123668417, 4946852336050088417, 141291773058735555757937, 141293528936024618797937 (list; graph; refs; listen; history; 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. 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

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.

Sequence in context: A120288 A099370 A118641 * A136541 A183551 A114071

Adjacent sequences:  A111919 A111920 A111921 * A111923 A111924 A111925

KEYWORD

nonn,frac

AUTHOR

Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Aug 21 2005

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Last modified February 14 17:27 EST 2012. Contains 205644 sequences.