A167558 The second right hand column of triangle A167557.

1, 12, 160, 2688, 55296, 1351680, 38338560, 1238630400, 44920995840, 1807409479680, 79906524364800, 3850733459865600, 200907832688640000, 11282983883794022400, 678650586195610828800, 43527244493925384192000

Offset

2,2

Comments

Triangle A167557 is the lower left triangle of the ED1 array A167546.

Links

G. C. Greubel, Table of n, a(n) for n = 2..150

A. Ryabov, P. Chvosta, Tracer dynamics in a single-file system with absorbing boundary, arXiv preprint arXiv:1402.1949 [cond-mat.stat-mech], 2014.

Formula

a(n) = 4^(n-2)*(n-2)!*(2*n-3)!/(2*n-4)!.

(-2*n+5)*a(n) +4*(2*n-3)*(n-2)*a(n-1)=0. - R. J. Mathar, Apr 01 2015

Mathematica

Table[4^(n-2) (n-2)! (2n-3)!/(2n-4)!, {n, 2, 20}] (* Harvey P. Dale, Aug 21 2013 *)

Crossrefs

A167546 is the ED1 array.

Equals the second right hand column of triangle A167557.

Sequence in context: A208791 A019578 A144346 * A048609 A048603 A275040

Adjacent sequences: A167555 A167556 A167557 * A167559 A167560 A167561

Keyword

easy,nonn

Author

Johannes W. Meijer, Nov 10 2009

Status

approved