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A144667 Decimal expansion of product_{n=2..infinity} (n^8-1)/(n^8+1). 1

%I

%S 9,9,1,8,7,8,4,0,7,6,5,8,2,9,4,8,1,6,9,6,6,4,2,6,9,2,7,7,8,4,8,8,9,3,

%T 4,0,4,8,0,4,0,6,2,9,2,0,6,6,3,5,4,2,2,8,7,4,5,0,5,8,3,0,7,6,1,9,5,8,

%U 1,8,4,1,2,5,0,3,9,1,6,8,5,9,7,3,1,0,8,1,8,9,9,1,6,2,5,0,8,8,3,6,7,0,7,2,8

%N Decimal expansion of product_{n=2..infinity} (n^8-1)/(n^8+1).

%H J. Borwein et al., <a href="http://www.ams.org/mathscinet-getitem?mr=2051473">Experimentation in Mathematics</a>, 2004, section 1.2.

%H E. W. Weisstein, <a href="http://mathworld.wolfram.com/InfiniteProduct.html">Infinite Product</a>, MathWorld.

%e 0.9918784076582948169664...

%t RealDigits[-1/4*Pi*Csc[(-1)^(1/8)*Pi]*Csc[(-1)^(3/8)*Pi]*Csc[(-1)^(5/8)*Pi] * Csc[(-1)^(7/8)*Pi]*Sin[(-1)^(1/4)*Pi]*Sin[(-1)^(3/4)*Pi]*Sinh[Pi] // Re, 10, 105] // First (* _Jean-Fran├žois Alcover_, Feb 11 2013 *)

%Y Cf. A090986.

%K nonn,cons

%O 0,1

%A _R. J. Mathar_, Feb 01 2009

%E More terms from _Jean-Fran├žois Alcover_, Feb 11 2013

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Last modified January 17 12:45 EST 2020. Contains 330958 sequences. (Running on oeis4.)