OFFSET
1,3
REFERENCES
Jean-François Pabion, Éléments d'Analyse Complexe, licence de Mathématiques, page 111, Ellipses, 1995.
LINKS
Philippe Flajolet and Robert Sedgewick, Analytic Combinatorics, Cambridge Univ. Press, 2009, pp. 235-236.
FORMULA
Equals Integral_{x=0..oo} 1/(1 + x^8) dx.
Equals Pi*csc(Pi/8)/8.
Equals 1/Product_{k>=1} (1 - 1/(8*k)^2). - Amiram Eldar, Mar 12 2022
Equals Product_{k>=2} (1 + (-1)^k/A047522(k)). - Amiram Eldar, Nov 22 2024
EXAMPLE
1.02617215297703088887146778087283197497962...
MATHEMATICA
First[RealDigits[N[Pi*Sqrt[2]Sqrt[2+Sqrt[2]]/8, 95]]]
PROG
(PARI) Pi*sqrt(4 + 2*sqrt(2))/8 \\ Michel Marcus, Mar 07 2022
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Stefano Spezia, Mar 05 2022
STATUS
approved