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0,1
Also the negated imaginary part of Gamma(i).
Table of n, a(n) for n=0..104.
Sykora S., Mathematical Constants, Stan's Library, Vol.II
Wikipedia, Particular values of the Gamma function
i! = gamma(1+i) = i*gamma(i).
0.498015668118356042713691117462198...
RealDigits[Re[Gamma[I + 1]], 10, 105] (* T. D. Noe, May 29 2012 *)
(PARI) real(I*gamma(I))
Cf. A212878 (-imag(i!)), A212879 (abs(i!)), A212880 (-arg(i!)).
Sequence in context: A154684 A256174 A096982 * A205297 A159643 A200398
Adjacent sequences: A212874 A212875 A212876 * A212878 A212879 A212880
nonn,cons,easy
Stanislav Sykora, May 29 2012
approved