A177311 Number of permutations of 8 copies of 1..n with all adjacent differences <= 2 in absolute value.

1, 1, 12870, 9465511770, 580132098966420, 19840440079542390102, 1061489454895820193068774

Offset: 0

Author

R. H. Hardin, May 06 2010

Keywords

• nonn

Comments

a(n) = (8n)!/40320^n for n<=3.

Crossrefs

Cf. A172609.