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Search: id:A086891
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| A086891 |
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Denominator of 4*(Integral_{x=0..1} (1-x^2)^((2n-1)/2) dx)/Pi. |
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+0 2
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| 1, 4, 8, 64, 640, 2560, 35840, 114688, 688128, 13762560, 14417920, 346030080, 1799356416, 2399141888, 23991418880, 767725404160, 2372969431040, 5695126634496, 216414812110848, 221963909857280, 9322484214005760
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OFFSET
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1,2
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EXAMPLE
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a(2)=4.
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MATHEMATICA
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f[n_] := Denominator[ 3Simplify[ Sqrt[2]((Integrate[(1 + x^2)^((2n - 1)/2), {x, 0, 1}]) - (2n - 1)!!ArcSinh[1]/(2n)!!)]]; Table[ f[n], {n, 1, 21}] (from Robert G. Wilson v Feb 27 2004)
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CROSSREFS
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Cf. A076729 and A087547.
Sequence in context: A120777 A091095 A075787 this_sequence A117636 A051226 A013112
Adjacent sequences: A086888 A086889 A086890 this_sequence A086892 A086893 A086894
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KEYWORD
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frac,nonn
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AUTHOR
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Al Hakanson (hawkuu(AT)excite.com), Sep 18 2003
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EXTENSIONS
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More terms from Robert G. Wilson v (rgwv(AT)rgwv.com), Feb 27 2004
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