%I
%S 1,4,7,8,9,4,2,8,5,7,5,4,4,5,9,7,4,3,3,8,2,7,9,0,6,0,1,9,4,3,3,9,1,4,
%T 4,3,5,0,7,1,6,9,7,4,3,0,5,9,5,0,0,8,2,5,1,8,8,1,2,1,2,2,4,9,3,3,5,3,
%U 8,3,3,6,3,5,2,5,0,6,8,7,8,0,5,1,6,2
%N Decimal expansion of arclength from (0,0) to (1,1) on y = x^2.
%F arclength = (2 sqrt(5) + arcsinh(2))/4.
%F arclength = (2 sqrt(5) + log(2 + sqrt(5)))/4.
%e Equals 1.478942857544597433827906...
%t s = Integrate[Sqrt[1 + 4 x^2], {x, 0, 1}]
%t r = N[s, 200]
%t RealDigits[r][[1]]
%Y Cf. A333203, A333204, A335996.
%K nonn,cons,easy
%O 1,2
%A _Clark Kimberling_, May 13 2020
