cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A181609 Kendell-Mann numbers in terms of Mahonian distribution.

Original entry on oeis.org

2, 3, 7, 23, 108, 604, 3980, 30186, 258969, 2479441, 26207604, 303119227, 3807956707, 51633582121, 751604592219, 11690365070546, 193492748067369, 3395655743755865, 62980031819261211, 1230967683216803500
Offset: 2

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Author

Mikhail Gaichenkov, Jan 30 2011

Keywords

Comments

It is well known that the variance of the Mahonian distribution is equal to sigma^2=n(n-1)(2n+5)/72. It is possible to have the asymptotic expansion for Kendell-Mann numbers M(n)=n!/sigma * 1/sqrt(2*Pi) * (1 - 2/(3*n) + O(1/n^2)). This results in M(n+1)/M(n)=n-1/2+O(1/n) as n--> infinity. [corrected by Vaclav Kotesovec, May 17 2015]

Examples

			M(2)=2, M(3)=3, M(4)=7,...
		

Crossrefs

Cf. A000140.

Formula

M(n) = Round(n!/sqrt(Pi*n(n-1)(2n+5)/36)).