A177313 Number of permutations of 9 copies of 1..n with all adjacent differences <= 1 in absolute value.

1, 1, 48620, 60110030, 161686253810, 304100156874800, 574996024253854586, 1016915629343040544250, 1745708356607370063330620, 2911820015993491302722966990, 4754502826758413615581742528138, 7626389809822483147908697112197520, 12055478550658617275428327115583119762

Offset: 0

Author

R. H. Hardin, May 06 2010

Keywords

• nonn

Comments

a(n) = (9n)!/362880^n = A172613(n) for n<=2.

Links

• Andrew Howroyd, Table of n, a(n) for n = 0..200

Crossrefs

Column k=9 of A331562.

Cf. A172613.

Extensions

a(0)=1 prepended by Alois P. Heinz, Jan 20 2020

Terms a(7) and beyond from Andrew Howroyd, May 15 2020