A212879 Decimal expansion of the absolute value of i!.

5, 2, 1, 5, 6, 4, 0, 4, 6, 8, 6, 4, 9, 3, 9, 8, 4, 1, 1, 5, 8, 1, 8, 0, 2, 6, 9, 6, 2, 8, 1, 9, 0, 0, 5, 3, 8, 5, 6, 4, 0, 5, 6, 7, 8, 2, 7, 7, 8, 9, 5, 6, 3, 1, 9, 2, 5, 5, 6, 8, 1, 2, 2, 4, 4, 4, 2, 4, 8, 6, 9, 5, 2, 3, 6, 2, 2, 8, 0, 8, 1, 6, 5, 4, 1, 1, 2, 7, 4, 9, 3, 6, 6, 7, 5, 2, 4, 1, 0, 9, 6, 6, 5, 3, 7

Offset: 0

Author

Stanislav Sykora, May 29 2012

Keywords

• nonn
• cons
• easy

Comments

Also absolute value of Gamma(i).

Examples

			0.5215640468649398411581802696...
		

Links

• G. C. Greubel, Table of n, a(n) for n = 0..5000

Crossrefs

Cf. A090986, A212877 (real(i!)), A212878 (-imag(i!)), A212880 (-arg(i!)).

Programs

Mathematica

N[Sqrt[Pi/Sinh[Pi]], 103] (* Vaclav Kotesovec, Dec 10 2015 *)
RealDigits[Abs[I!], 10, 120][[1]] (* Amiram Eldar, Oct 25 2024 *)

PARI

abs(gamma(I))

Formula

Equals abs(Gamma(i)), since i! = Gamma(1+i) = i*Gamma(i).

Equals sqrt(Pi/sinh(Pi)). - Vaclav Kotesovec, Dec 10 2015

Equals Product_{k>=1} k/sqrt(k^2+1) = sqrt(A090986). - Amiram Eldar, Oct 25 2024