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A333205
Decimal expansion of arclength between inflection points of y = 1/(1 + x^2).
1
1, 2, 7, 6, 4, 8, 5, 0, 4, 3, 5, 7, 7, 2, 1, 9, 0, 7, 9, 5, 0, 5, 7, 8, 8, 1, 0, 3, 2, 6, 5, 2, 2, 0, 2, 0, 8, 9, 7, 8, 9, 8, 2, 3, 6, 7, 9, 9, 7, 6, 8, 4, 1, 1, 9, 8, 1, 6, 7, 9, 7, 5, 4, 6, 2, 5, 4, 9, 4, 7, 4, 4, 2, 7, 0, 8, 3, 8, 0, 3, 3, 9, 9, 5, 1, 1
OFFSET
1,2
EXAMPLE
arclength = 1.2764850435772190795057881032652202089789823679976841...
MATHEMATICA
s = Integrate[Sqrt[1 + 4 x^2/(1 + x^2)^4], {x, -Sqrt[1/3], Sqrt[1/3]}]
r = N[s, 200]
RealDigits[r][[1]]
CROSSREFS
Sequence in context: A175477 A333521 A359533 * A011263 A074067 A110988
KEYWORD
nonn,cons,easy
AUTHOR
Clark Kimberling, Jun 12 2020
STATUS
approved