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 A226284 #15 Jul 12 2024 15:19:12
%S A226284 0,0,0,0,0,36,576,9216,115200,1440000,17280000,207360000,2540160000,
%T A226284 31116960000,398297088000,5098202726400,68825736806400,
%U A226284 929147446886400,13273534955520000,189621927936000000,2868031660032000000,43378978857984000000,694063661727744000000
%N A226284 a(n) = [n/2]!*[(n+1)/2]!*C([n/2],3)*C([(n+1)/2],3).
%C A226284 Number of permutations of n elements with 6 odd displacements.
%C A226284 Column 4 of A226288.
%C A226284 Column k=6 of A145893, a diagonal of A145894. - _Alois P. Heinz_, May 29 2014
%H A226284 R. H. Hardin, <a href="/A226284/b226284.txt">Table of n, a(n) for n = 1..210</a>
%t A226284 Table[Floor[n/2]!Floor[(n+1)/2]!Binomial[Floor[n/2],3]Binomial[Floor[ (n+1)/2], 3],{n,30}] (* _Harvey P. Dale_, Dec 12 2018 *)
%Y A226284 Cf. A145893, A145894, A226288.
%K A226284 nonn
%O A226284 1,6
%A A226284 _R. H. Hardin_, connection of formula with combinatoric problem via _N. J. A. Sloane_ in the Sequence Fans Mailing List, Jun 02 2013