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A111920 Numerator of x(n) = Sum((odd part of k)/(k^4): 1<=k<=n). 5
1, 17, 475, 7627, 960287, 962287, 330928441, 5296012681, 143167958387, 143231970419, 190769776691689, 190794429473689, 419345761582878733, 419413977483774733, 16780996063666453, 268499592964601893 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

Denominator of x(n) = A111921(n);

x(n) = a(n)/A111921(n) -> 14*zeta(3)/15.

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, Apery's constant

Eric Weisstein's World of Mathematics, Riemann Zeta Function

EXAMPLE

a(35) = 6357636538031086038114593391432155018318189,

A111921(35) = 5668063317569576031821812156438757376000000:

x(35)=a(35)/A111921(35)=1.12165..., x(35)*15/14=1.20177....

CROSSREFS

Cf. A000265, A002117, A111929, A111918, A111922.

Sequence in context: A035276 A196484 A196717 * A166116 A173148 A142368

Adjacent sequences:  A111917 A111918 A111919 * A111921 A111922 A111923

KEYWORD

nonn,frac

AUTHOR

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

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Last modified February 16 21:51 EST 2012. Contains 205978 sequences.