

A090598


Numerator of ((integral_{x = 0..1/2} 1/(1+x^2)^(n + 1/2) dx) * sqrt(1/5)).


0



1, 14, 328, 10800, 458880, 23911680, 1477278720, 105623562240, 8582728089600, 781478859571200, 78834419151667200, 8729454895025356800, 1052840115930503577600, 137399767923711541248000
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OFFSET

1,2


COMMENTS

Denominator is b(n)=5^(n1)*(2*n)!/(n!*2^n). E.g. b(3)=375.


LINKS

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


EXAMPLE

E.g. a(3) = 328 since f(n) = 328/375.


MATHEMATICA

f[n_] := (5^(n  1/2)(2n  1)!!Integrate[1/(1 + x^2)^(n + 1/2), {x, 0, 1/2}]); Table[ f[n], {n, 1, 15}] (from Robert G. Wilson v Feb 27 2004)


CROSSREFS

Sequence in context: A035018 A133130 A241373 * A060075 A222984 A035273
Adjacent sequences: A090595 A090596 A090597 * A090599 A090600 A090601


KEYWORD

nonn,frac


AUTHOR

Al Hakanson (hawkuu(AT)excite.com), Feb 25 2004


EXTENSIONS

Edited and extended by Robert G. Wilson v, Feb 27 2004


STATUS

approved



