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

1,1

Comments

Column 5 of A189449.

Links

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

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

Example

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

Crossrefs

Cf. A189449.

Sequence in context: A013377 A214383 A220546 * A193786 A213799 A316809

Adjacent sequences: A189442 A189443 A189444 * A189446 A189447 A189448

Keyword

nonn

Author

R. H. Hardin, Apr 22 2011

Status

approved