A144666 - OEIS

A144666

Decimal expansion of product_{n=2..infinity} (n^7-1)/(n^7+1).

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

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OFFSET

0,1

LINKS

Table of n, a(n) for n=0..104.

J. Borwein et al., Experimentation in Mathematics, 2004, section 1.2.

E. W. Weisstein, Infinite Product, MathWorld.

EXAMPLE

0.9834397805869282351144875535540...

MATHEMATICA

p = 2*Product[Gamma[2+(-1)^(k+k/7)], {k, 6}]/Product[Gamma[2-(-1)^(k+k/7)], {k, 6}]; RealDigits[Re[p], 10, 105][[1]] (* Jean-François Alcover, Feb 11 2013, updated Nov 18 2015 *)

RealDigits[Re[N[Product[(n^7 - 1)/(n^7 + 1), {n, 2, Infinity}], 110]]][[1]] (* Bruno Berselli, Apr 02 2013 *)

CROSSREFS

Cf. A090986.

Sequence in context: A343359 A210649 A347331 * A255251 A363633 A224236

Adjacent sequences: A144663 A144664 A144665 * A144667 A144668 A144669

KEYWORD

nonn,cons

AUTHOR

R. J. Mathar, Feb 01 2009

EXTENSIONS

More terms from Jean-François Alcover, Feb 11 2013

STATUS

approved