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A095175

Denominator of b(n) given by b(1) = 1, b(2) = 2; for n >= 3, b(n) = (-1)^n (2n-1) ((n-2)!!)^2/((n-1)!!)^2, where n!! is the double factorial A006882.

1, 1, 4, 9, 64, 225, 256, 245, 16384, 99225, 65536, 480249, 1048576, 1002001, 4194304, 41409225, 1073741824, 2393453205, 4294967296, 4102737925, 68719476736, 940839860961, 274877906944, 4113258565689, 17592186044416, 16802526820625, 70368744177664

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OFFSET

1,3

COMMENTS

A095159(2n)/a(2n) -> pi as n -> inf.; A095159(2n+1)/a(2n+1) -> -4/pi as n -> inf. - Leroy Quet, Aug 03 2004

LINKS

Table of n, a(n) for n=1..27.

CROSSREFS

Cf. A006882, A095159.

Sequence in context: A069711 A062067 A110256 * A092396 A184877 A055859

Adjacent sequences: A095172 A095173 A095174 * A095176 A095177 A095178

KEYWORD

nonn,frac

AUTHOR

N. J. A. Sloane, based on a suggestion of Leroy Quet, Jul 03 2004

STATUS

approved