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A295709
Decimal expansion of the arc length of the loop of the Folium of Descartes, a curve given by x^3 + y^3 = 3axy, with a = 1.
3
4, 9, 1, 7, 4, 8, 8, 7, 2, 1, 6, 8, 1, 5, 3, 3, 5, 0, 9, 9, 3, 7, 8, 7, 7, 2, 3, 7, 3, 4, 8, 7, 1, 8, 7, 0, 9, 0, 1, 3, 8, 0, 3, 7, 8, 8, 4, 3, 3, 0, 5, 5, 3, 0, 9, 4, 6, 1, 0, 2, 8, 1, 5, 4, 5, 1, 5, 1, 2, 9, 3, 0, 1, 3, 3, 4, 9, 2, 1, 0, 8, 6, 7, 7, 9, 3, 5
OFFSET
1,1
COMMENTS
The arc length for general value of "a" is 4.917...*a.
LINKS
Eric Weisstein's World of Mathematics, Folium of Descartes.
EXAMPLE
4.91748872168153350993...
MATHEMATICA
RealDigits[3*N[Integrate[Sqrt[1+x^2(4-4x-4x^3+4x^4+x^6)]/(1+x^3)^2, {x, 0, Infinity}], 100], 10][[1]]
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Amiram Eldar, Nov 26 2017
STATUS
approved