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A068215 Denominator of Borwein integral of order 2n+1. 4
2, 6, 30, 210, 1890, 20790, 270270, 1896516717212415135141110350293750000, 1220462921565155916674902677397230198502690752000000000 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..8.

Eric Weisstein's World of Mathematics, Borwein Integrals

Wikipedia, Borwein integral [From N. J. A. Sloane, Feb 25 2012]

FORMULA

a(n) = A144616(n+1)*A097801(n+1). - Andrey Zabolotskiy, Oct 18 2016

MATHEMATICA

i[n_] := Times@@(Sin[x/# ]&/@Range[1, n, 2])/x^((n+1)/2)/Pi; Denominator[Table[Integrate[i[n], {x, 0, \[Infinity]}], {n, 1, 19, 2}]]

CROSSREFS

Cf. A068214 (numerators), A144616 (denominators of the Borwein integrals defined in a different way).

Sequence in context: A127482 A118747 A129779 * A305400 A096775 A331665

Adjacent sequences:  A068212 A068213 A068214 * A068216 A068217 A068218

KEYWORD

nonn,frac,nice

AUTHOR

Eric W. Weisstein, Feb 21 2002

STATUS

approved

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Last modified June 17 05:25 EDT 2021. Contains 345080 sequences. (Running on oeis4.)