A177300 Number of permutations of 4 copies of 1..n with all adjacent differences <= 3 in absolute value.

1, 1, 70, 34650, 63063000, 42251309100, 17268436078740, 6595449547140990, 2941134289344290882

Offset: 0

Author

R. H. Hardin, May 06 2010

Keywords

• nonn

Comments

a(n) = (4n)!/24^n for n<=4.

Crossrefs

Cf. A014608.