A302304 Number of nX3 0..1 arrays with every element equal to 0, 1, 3 or 4 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

3, 11, 13, 33, 58, 153, 336, 937, 2449, 6560, 18488, 52053, 147896, 425764, 1229112, 3561761, 10353391, 30135225, 87835075, 256217794, 747737289, 2183170380, 6375689391, 18622164403, 54399493814, 158924553086, 464309179701

Offset

1,1

Comments

Column 3 of A302309.

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 3*a(n-1) -2*a(n-2) +13*a(n-3) -23*a(n-4) +13*a(n-5) -42*a(n-6) +25*a(n-7) -21*a(n-8) -36*a(n-9) +48*a(n-10) -24*a(n-11) +8*a(n-12) +32*a(n-13) for n>16

Example

Some solutions for n=5
..0..1..0. .0..1..0. .0..1..1. .0..1..0. .0..1..0. .0..0..1. .0..1..0
..1..1..0. .0..1..0. .1..0..1. .1..1..0. .0..1..0. .0..1..0. .1..1..0
..1..1..1. .0..1..0. .0..0..0. .0..1..0. .1..1..0. .1..1..1. .1..1..1
..1..1..0. .0..1..1. .0..0..1. .0..1..0. .0..1..0. .0..1..1. .0..1..0
..0..1..0. .0..1..0. .1..0..1. .1..0..0. .0..0..0. .0..1..0. .1..0..0

Crossrefs

Cf. A302309.

Sequence in context: A244047 A020451 A018450 * A119145 A168454 A181086

Adjacent sequences: A302301 A302302 A302303 * A302305 A302306 A302307

Keyword

nonn

Author

R. H. Hardin, Apr 05 2018

Status

approved