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A332631
Decimal expansion of arclength between (0,1) and (1,1/e) on y = 1/e^x.
1
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, 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, 7, 5, 6, 6, 4, 5, 5, 5, 5, 2, 7, 8, 9, 6, 4, 6, 3, 4
OFFSET
1,3
FORMULA
arclength = sqrt(2) = sqrt(1+ 1/e^2) + arcsinh(e) - arcsinh(1).
EXAMPLE
arclength = 1.192701401972154592777794219819503064418488768866...
MATHEMATICA
s = Integrate[Sqrt[1 + D[E^(-x), x]^2], {x, 0, 1}]
r = N[s, 200]
RealDigits[r][[1]]
CROSSREFS
Sequence in context: A275647 A011436 A248317 * A179638 A224268 A019877
KEYWORD
nonn,cons,easy
AUTHOR
Clark Kimberling, Jun 12 2020
STATUS
approved