A226287 - OEIS

A226287

a(n) = [n/2]!*[(n+1)/2]!*C([n/2],6)*C([(n+1)/2],6).

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 518400, 25401600, 1244678400, 39829708800, 1274550681600, 34412868403200, 929147446886400, 23228686172160000, 580717154304000000, 14053355134156800000, 340091194246594560000

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OFFSET

1,12

COMMENTS

Number of permutations of n elements with 12 odd displacements.

Column 7 of A226288.

Column k=12 of A145893, a diagonal of A145894. - Alois P. Heinz, May 29 2014

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

CROSSREFS

Sequence in context: A255034 A256952 A234173 * A251834 A157803 A236095

Adjacent sequences: A226284 A226285 A226286 * A226288 A226289 A226290

KEYWORD

nonn

AUTHOR

R. H. Hardin, connection of formula with combinatoric problem via N. J. A. Sloane in the Sequence Fans Mailing List, Jun 02 2013

STATUS

approved