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.
%I A181609 #20 May 18 2015 08:24:49 %S A181609 2,3,7,23,108,604,3980,30186,258969,2479441,26207604,303119227, %T A181609 3807956707,51633582121,751604592219,11690365070546,193492748067369, %U A181609 3395655743755865,62980031819261211,1230967683216803500 %N A181609 Kendell-Mann numbers in terms of Mahonian distribution. %C A181609 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] %H A181609 Mikhail Gaichenkov, <a href="http://mathoverflow.net/questions/46368/the-property-of-kendall-mann-numbers">The property of Kendall-Mann numbers</a>, answered by Richard Stanley, 2010 %H A181609 Mikhail Gaichenkov, <a href="http://mathoverflow.net/questions/73962/a-combinatorial-proof-for-the-property-of-km-numbers">A combinatorial proof for the property of KM numbers?</a> %F A181609 M(n) = Round(n!/sqrt(Pi*n(n-1)(2n+5)/36)). %e A181609 M(2)=2, M(3)=3, M(4)=7,... %Y A181609 Cf. A000140. %K A181609 nonn %O A181609 2,1 %A A181609 _Mikhail Gaichenkov_, Jan 30 2011