A066979 a(n) = floor(n!/2^n).

0, 0, 0, 1, 3, 11, 39, 157, 708, 3543, 19490, 116943, 760134, 5320940, 39907054, 319256437, 2713679718, 24423117468, 232019615953, 2320196159531, 24362059675078, 267982656425859, 3081800548897382, 36981606586768593

Offset: 1

Author

Benoit Cloitre, Jan 26 2002

Keywords

• nonn

Links

• Harry J. Smith, Table of n, a(n) for n = 1..150

Programs

Mathematica

Table[Floor[n!/2^n],{n,30}] (* Harvey P. Dale, Aug 21 2021 *)

PARI

a(n) = { n!\2^n } \\ Harry J. Smith, Apr 14 2010