gamma function

(definition)

Definition: The gamma function of n, written Γ(n), is ∫ ₀^∞ e^-xx^n-1dx. Recursively Γ(n+1) = nΓ(n). For non-negative integers Γ(n+1) = n!.

See also Stirling's formula.

Note: The gamma function is defined for all numbers whereas factorial is (strictly) only defined for non-negative integers.

Author: PEB

More information

MathWorld's gamma function

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Entry modified 17 December 2004.
HTML page formatted Tue Dec 6 16:16:32 2011.

Cite this as:
Paul E. Black, "gamma function", in Dictionary of Algorithms and Data Structures [online], Paul E. Black, ed., U.S. National Institute of Standards and Technology. 17 December 2004. (accessed TODAY) Available from: http://www.nist.gov/dads/HTML/gammaFunction.html