OFFSET
1,2
EXAMPLE
arclength = 1.277978059277934418567056623029833449721770...
MATHEMATICA
s = Integrate[Sqrt[1 + D[Tan[x], x]^2], {x, 0, Pi/4}]
r = N[s, 200]
RealDigits[r][[1]]
CROSSREFS
KEYWORD
AUTHOR
Clark Kimberling, Jun 12 2020
STATUS
approved