A174082 Number of circular permutations of length n with no consecutive triples i,i+d,i+2d for all d.

5, 18, 91, 544, 3842, 30573

Offset

4,1

Comments

Circular permutations are permutations whose indices are from the ring of integers modulo n.

Links

Table of n, a(n) for n=4..9.

Example

For n=4 there is only (3-1)!-a(4)=1 circular permutation with a consecutive triple i,i+d,i+2d. It is (0,1,2,3).

Crossrefs

Cf. A078628, A174074, A174080, A174081, A174083.

Sequence in context: A009305 A097574 A113023 * A188329 A165962 A127756

Adjacent sequences: A174079 A174080 A174081 * A174083 A174084 A174085

Keyword

nonn

Author

Isaac Lambert, Mar 15 2010

Status

approved