OFFSET
0,1
LINKS
E. Weisstein, Infinite Product, Mathworld.
FORMULA
Equals (cosh(sqrt(2)*Pi) - cos(sqrt(2)*Pi)) * sinh(Pi) / (16*Pi^3). - Vaclav Kotesovec, Apr 27 2020
Equals exp(Sum_{j>=1} (1 - zeta(8*j))/j). - Vaclav Kotesovec, Apr 27 2020
EXAMPLE
0.9959233150... = (255/256)*(6560/6561)*(65535/65536)*...
MAPLE
t := Pi/sqrt(2) ; sinh(Pi)*((sin(t)*cosh(t))^2+(cos(t)*sinh(t))^2)/8/Pi^3 ; evalf(%) ;
MATHEMATICA
RealDigits[ -Sin[(-1)^(1/4)*Pi]*Sin[(-1)^(3/4)*Pi]*Sinh[Pi] / (8*Pi^3) // Re, 10, 105] // First(* Jean-François Alcover, Feb 12 2013 *)
PROG
(PARI) exp(suminf(j=1, (1 - zeta(8*j))/j)) \\ Vaclav Kotesovec, Apr 27 2020
CROSSREFS
KEYWORD
AUTHOR
R. J. Mathar, Jul 26 2010
STATUS
approved