Multifactorial

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A generalization of the factorial and double factorial,

			(1)
			(2)
			(3)

etc., where the products run through positive integers.

The following table lists the values of the first few multifactorials for , 2, ....

	A000142	1, 2, 6, 24, 120, 720, ...
	A006882	1, 2, 3, 8, 15, 48, 105, ...
	A007661	1, 2, 3, 4, 10, 18, 28, 80, 162, 280, ...
	A007662	1, 2, 3, 4, 5, 12, 21, 32, 45, 120, ...

See also

Double Factorial, Factorial, Gamma Function, Pochhammer Symbol, Reciprocal Multifactorial Constant

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References

Sloane, N. J. A. Sequences A000142/M1675, A006882/M0876, A007661/M0596, and A007662/M0534 in "The On-Line Encyclopedia of Integer Sequences."

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Cite this as:

Weisstein, Eric W. "Multifactorial." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Multifactorial.html

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