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A333203
Decimal expansion of arclength from (0,0) to (1,1) on y = x^3.
3
1, 5, 4, 7, 8, 6, 5, 6, 5, 4, 6, 8, 3, 6, 1, 0, 1, 4, 4, 7, 7, 5, 3, 3, 1, 6, 4, 6, 0, 6, 4, 2, 6, 0, 6, 1, 8, 0, 0, 6, 6, 3, 3, 3, 1, 7, 9, 4, 7, 0, 7, 2, 2, 5, 1, 3, 6, 8, 5, 9, 3, 9, 1, 6, 5, 5, 0, 2, 1, 1, 1, 4, 1, 2, 3, 2, 6, 0, 0, 7, 2, 6, 6, 9, 3, 1
OFFSET
1,2
FORMULA
arclength = 2F1(-1/2;1/4;5/4;-9), where 2F1 is the hypergeometric function.
EXAMPLE
arclength = 1.54786565468361014477533164606426061800663...
MATHEMATICA
s = Integrate[Sqrt[1 + 9 x^4], {x, 0, 1}]
r = N[s, 200]
RealDigits[r][[1]]
PROG
(PARI) intnum(x=0, 1, sqrt(1+9*x^4)) \\ Michel Marcus, Jun 12 2020
CROSSREFS
Sequence in context: A111421 A324021 A323983 * A340705 A252666 A378823
KEYWORD
nonn,cons,easy
AUTHOR
Clark Kimberling, Jun 12 2020
STATUS
approved