A157984 a(n) = n!/(7 * 20!).

3, 66, 1518, 36432, 910800, 23680800, 639381600, 17902684800, 519177859200, 15575335776000, 482835409056000, 15450733089792000, 509874191963136000, 17335722526746624000, 606750288436131840000, 21843010383700746240000

Offset

21,1

Comments

From calculations for a Witt design:

http://www.math.uic.edu/~ronan/Witt_design;

a(n)*8!/3! - 48*n!/19!

Links

Table of n, a(n) for n=21..36.

Mathematica

Flatten[Table[If[IntegerQ[48*3!*n!/(8!*19! )], 48*3!*n!/( 8!*19! ), {}], {n, 0, 48}]] (* Roger L. Bagula *)
Select[With[{n=48 3!, d=8! 19!}, Table[(n  i!)/d, {i, 50}]], IntegerQ] (* Harvey P. Dale, Jan 05 2011 *)
f[n_] := n!/(7 * 20!); Array[f, 10, 21] (* Robert G. Wilson v, Jan 05 2011 *)

Crossrefs

Sequence in context: A259457 A157543 A368596 * A187547 A157554 A185053

Adjacent sequences: A157981 A157982 A157983 * A157985 A157986 A157987

Keyword

nonn

Author

Roger L. Bagula, Mar 10 2009

Status

approved