A189447 Number of n X 7 array permutations with each element moving zero or one space horizontally or diagonally.

21, 3136, 313136, 33735505, 3586575040, 381987110556, 40668908306516, 4329976369716644, 461007230769131204, 49082883213353553796, 5225795314666113134276, 556384119909347581932164

Offset: 1

Author

R. H. Hardin Apr 22 2011

Keywords

• nonn

Comments

Column 7 of A189449.

Examples

			Some solutions for 3 X 7
..0..1..3..4.12..6..5....0..2..1..3..4.13..6....0..2..1..3..4.13..6
..7..9..8..2.10.20.13....7..8..9.10.11.12..5....7..8..9.10.11.12..5
.15.14.16.17.18.11.19...15.14.16.18.17.20.19...14.15.16.17.18.19.20
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..200

Crossrefs

Cf. A189449.

Formula

Empirical: a(n) = 119*a(n-1) -1238*a(n-2) -11504*a(n-3) +132848*a(n-4) +180912*a(n-5) -203520*a(n-6) +1542400*a(n-7) +2403200*a(n-8) -768000*a(n-9) +640000*a(n-10) for n>14.