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A217909
Decimal expansion of (Pi-3)*(2*Pi-3)/4.
2
1, 1, 6, 2, 1, 8, 7, 2, 9, 9, 6, 7, 6, 4, 4, 5, 2, 2, 8, 7, 6, 2, 9, 7, 8, 8, 7, 5, 5, 9, 1, 9, 4, 0, 7, 8, 2, 1, 3, 2, 1, 8, 5, 5, 5, 0, 2, 6, 4, 0, 7, 2, 1, 6, 0, 1, 3, 0, 4, 9, 3, 5, 5, 4, 1, 7, 4, 3, 5, 4, 9, 7, 0, 6, 5, 6, 3, 2, 3, 7, 4, 5, 8, 7, 8, 0, 8
OFFSET
0,3
REFERENCES
Tom M. Apostol, Calculus, Vol. 1, John Wiley & Sons, 1967 (2nd ed.). This constant is the case s=t=3 in sum(sin(n*s)/n^t, n>=1), see p. 409.
FORMULA
Equals sum(sin(3*k)/k^3, k>=1).
EXAMPLE
0.1162187299676445228762978875591940782132185550264072...
MATHEMATICA
RealDigits[(Pi - 3) (2 Pi - 3)/4, 10, 90][[1]]
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Bruno Berselli, Mar 25 2013
STATUS
approved