OFFSET
1,1
REFERENCES
Jonathan Borwein, David Bailey and Roland Girgensohn, Experimentation in Mathematics: Computational Paths to Discovery, A K Peters, 2004, p. 20.
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..5000
Eric Weisstein's World of Mathematics, Ahmed's Integral
FORMULA
Equals Pi/4 - Pi/sqrt(2) + (3*arctan(sqrt(2)))/sqrt(2).
Equals Integral_{x=0..1} arctan(sqrt(x^2 + 1))/(x^2 + 1)^(3/2) dx (Borwein et al., 2004). - Amiram Eldar, Aug 17 2020
EXAMPLE
0.590489270886385075159298139571568463546513361355639...
MATHEMATICA
RealDigits[Pi/4 - Pi/Sqrt[2] + (3*ArcTan[Sqrt[2]])/Sqrt[2], 10, 50][[1]] (* G. C. Greubel, Jun 02 2017 *)
PROG
(PARI) Pi/4 - Pi/sqrt(2) + (3*atan(sqrt(2)))/sqrt(2) \\ G. C. Greubel, Jun 02 2017
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Eric W. Weisstein, Jan 14 2005
STATUS
approved