A189445 Number of n X 5 array permutations with each element moving zero or one space horizontally or diagonally.

8, 225, 5080, 118128, 2735828, 63367633, 1467726607, 33995627281, 787410049440, 18238068717816, 422431934648884, 9784409861152809, 226627459902104327, 5249167431711452449, 121581730378315708936, 2816087951868941718112

Offset: 1

Author

R. H. Hardin, Apr 22 2011

Keywords

• nonn

Comments

Column 5 of A189449.

Examples

			Some solutions for 3 X 5:
..1..7..3..2..4....6..7..2..9..4....0..2..8..9..4....0..1..3..2..4
..5..0.13..8..9....5..0..1..8..3....6..5..1..7..3....6..5..8..7..9
.11.10..6.12.14...10.12.11.13.14...10.11.12.13.14...10.12.11.14.13
		

Links

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

Crossrefs

Cf. A189449.

Formula

Empirical: a(n) = 24*a(n-1) -19*a(n-2) -11*a(n-3) +36*a(n-4) +3*a(n-5) for n>6.

Empirical g.f.: x*(8 + 33*x - 168*x^2 + 571*x^3 - 537*x^4 - 51*x^5) / ((1 + x)*(1 - 25*x + 44*x^2 - 33*x^3 - 3*x^4)). - Colin Barker, May 02 2018