A177310 Number of permutations of 8 copies of 1..n with all adjacent differences <= 1 in absolute value.

1, 1, 12870, 6077196, 5650739930, 3772321496064, 2514046004253110, 1570273521448103668, 951645881858020642746, 560523113474283819256640, 323221203836407773725200718, 183122229346363470922528553652, 102256611847518844993947706000234

Offset: 0

Author

R. H. Hardin, May 06 2010

Keywords

• nonn

Comments

a(n) = (8n)!/40320^n = A172609(n) for n<=2.

Links

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

Crossrefs

Column k=8 of A331562.

Cf. A172609.

Extensions

a(0)=1 prepended by Alois P. Heinz, Jan 21 2020

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