OFFSET
1,3
FORMULA
Equals Sum_{k>=0} cos(k*Pi/4)/2^k.
EXAMPLE
1.190743569830546185082650951331123190335824448595932...
MATHEMATICA
s = Sum[Cos[k Pi/4]/2^k, {k, 0, Infinity}]
d = N[s, 100]
u = First[RealDigits[d]]
N[1/17 (16 + 3 Sqrt[2]), 100]
CROSSREFS
KEYWORD
AUTHOR
Clark Kimberling, Jun 07 2024
STATUS
approved