1,2

Numbers for permutations of 0..2n-1 are zero.

Table of n, a(n) for n=1..8.

Sequence in context: A114371 A047802 A278705 * A079916 A204327 A123283

Adjacent sequences: A180234 A180235 A180236 * A180238 A180239 A180240

nonn

R. H. Hardin Aug 18 2010

approved