OFFSET
0,1
FORMULA
Equals Sum_{k>=0} tan(k*Pi/3)/3^k.
EXAMPLE
0.39970403251589476004479530957827823852526275087931860...
MATHEMATICA
s = Sum[Tan[k Pi/3]/3^k, {k, 0, Infinity}]
d = N[s, 100]
First[RealDigits[d]]
N[(3 Sqrt[3])/13, 100]
RealDigits[(3*Sqrt[3])/13, 10, 120][[1]] (* Harvey P. Dale, Jul 17 2024 *)
PROG
(Python)
from math import isqrt
def A372914(n): return isqrt(27*10**(n+1<<1)//169)%10 # Chai Wah Wu, Jul 08 2024
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Jul 01 2024
STATUS
approved