login
A177295
Number of permutations of 3 copies of 1..n with all adjacent differences <= 5 in absolute value.
0
1, 1, 20, 1680, 369600, 168168000, 137225088000, 67280653440000, 22859094527068800, 6325233865588881600
OFFSET
0,3
COMMENTS
a(n) = (3n)!/6^n for n<=6.
CROSSREFS
Cf. A014606.
Sequence in context: A177294 A177615 A177616 * A177635 A177296 A177297
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 06 2010
STATUS
approved