A177314 Number of permutations of 9 copies of 1..n with all adjacent differences <= 2 in absolute value.

1, 1, 48620, 227873431500, 66341857216154520, 10150867545062935511900

Offset

0,3

Comments

a(n) = (9n)!/362880^n for n<=3.

Links

Table of n, a(n) for n=0..5.

Crossrefs

Cf. A172613.

Sequence in context: A177313 A140924 A351488 * A177315 A172613 A172554

Adjacent sequences: A177311 A177312 A177313 * A177315 A177316 A177317

Keyword

nonn

Author

R. H. Hardin, May 06 2010

Status

approved