%I #6 Jul 08 2020 14:13:47
%S 7,6,3,9,2,6,6,6,3,3,1,7,0,9,1,0,4,1,1,6,1,9,6,0,9,1,8,8,8,4,0,9,2,4,
%T 3,5,0,7,4,9,5,6,6,3,5,8,1,8,4,2,8,7,9,1,8,4,8,5,9,8,9,1,4,3,0,4,3,6,
%U 3,7,6,2,9,0,1,3,4,6,2,5,4,6,2,2,3,1
%N Decimal expansion of the number u such that the arclength on y = x^2 from (0,0) to (u, u^2) is 1.
%e u = 0.763926663317091041161960918884092435074956...
%t x = x /.FindRoot[1/2 x Sqrt[1 + 4 x^2] + 1/4 ArcSinh[2 x] == 1, {x, 0}, WorkingPrecision -> 200]
%t RealDigits[x][[1]]
%Y Cf. A333202.
%K nonn,cons
%O 0,1
%A _Clark Kimberling_, Jul 04 2020