A180895 Number of permutations of 7..n+6 with no element greater than or equal to the sum of its neighbors

1, 0, 2, 6, 30, 180, 1260, 10080, 88200, 846360, 8704560, 96521328, 1136939886, 14300688576, 190022230230, 2677680493446, 39679534875572, 619978024613994

Offset

1,3

Links

Table of n, a(n) for n=1..18.

Crossrefs

Sequence in context: A293906 A180893 A180894 * A180896 A180897 A353184

Adjacent sequences: A180892 A180893 A180894 * A180896 A180897 A180898

Keyword

nonn

Author

R. H. Hardin Sep 23 2010

Status

approved