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Decimal expansion of arclength between (0,1) and (1,1/e) on y = 1/e^x.
1

%I #6 Jun 14 2020 22:49:16

%S 1,1,9,2,7,0,1,4,0,1,9,7,2,1,5,4,5,9,2,7,7,7,7,9,4,2,1,9,8,1,9,5,0,3,

%T 0,6,4,4,1,8,4,8,8,7,6,8,8,6,6,3,4,8,3,7,5,9,1,9,6,3,7,8,0,8,2,3,5,9,

%U 7,5,6,6,4,5,5,5,5,2,7,8,9,6,4,6,3,4

%N Decimal expansion of arclength between (0,1) and (1,1/e) on y = 1/e^x.

%F arclength = sqrt(2) = sqrt(1+ 1/e^2) + arcsinh(e) - arcsinh(1).

%e arclength = 1.192701401972154592777794219819503064418488768866...

%t s = Integrate[Sqrt[1 + D[E^(-x), x]^2], {x, 0, 1}]

%t r = N[s, 200]

%t RealDigits[r][[1]]

%Y Cf. A333202, A332629.

%K nonn,cons,easy

%O 1,3

%A _Clark Kimberling_, Jun 12 2020