A177309 Number of permutations of 7 copies of 1..n with all adjacent differences <= 3 in absolute value.

1, 1, 3432, 399072960, 472518347558400, 102038786510159790720, 9792481437399343532438160

Offset

0,3

Comments

a(n) = (7n)!/5040^n for n<=4.

Links

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

Crossrefs

Cf. A172603.

Sequence in context: A351486 A362172 A177308 * A172603 A172559 A172658

Adjacent sequences: A177306 A177307 A177308 * A177310 A177311 A177312

Keyword

nonn

Author

R. H. Hardin, May 06 2010

Status

approved