OFFSET
0,1
REFERENCES
L. B. W. Jolley, Summation of Series, Dover, 1961, Eq. (326).
FORMULA
Equals 1 + Sum_{k>=1} ( (-1)^k/(4*k-1) - (-1)^k/(4*k+1) ).
EXAMPLE
0.889279265460408438246029752484826575346344577656...
MAPLE
evalf(2-Pi/sqrt(8), 140); # Alois P. Heinz, Aug 06 2021
MATHEMATICA
RealDigits[2 - Pi / (2 * Sqrt[2]), 10, 120][[1]] (* Amiram Eldar, Jun 07 2023 *)
PROG
(PARI) 2 - Pi/(2*sqrt(2)) \\ Michel Marcus, Aug 06 2021
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Sean A. Irvine, Aug 06 2021
STATUS
approved