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

0,3

Comments

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

Links

Table of n, a(n) for n=0..6.

Crossrefs

Cf. A172609.

Sequence in context: A177310 A140917 A351487 * A177312 A172609 A172560

Adjacent sequences: A177308 A177309 A177310 * A177312 A177313 A177314

Keyword

nonn

Author

R. H. Hardin, May 06 2010

Status

approved