A170812 Number of permutations of 1..n with all differences of elements separated by distances 1 through 6 being respectively unique.

1, 2, 4, 12, 40, 116, 200, 444, 760, 2160, 4368, 7852, 12828, 17252, 21136, 28716, 37276, 53624, 76740, 114856, 180232, 290280

Offset

1,2

Comments

(Empirical) Equals A008404 for n<=2m+2, where m is the maximum difference separation 6.

Links

Table of n, a(n) for n=1..22.

Crossrefs

Sequence in context: A170815 A170814 A170813 * A170811 A170810 A170809

Adjacent sequences: A170809 A170810 A170811 * A170813 A170814 A170815

Keyword

nonn

Author

R. H. Hardin Dec 02 2009

Status

approved