A298714 Number of nX3 0..1 arrays with every element equal to 2, 3, 4, 6 or 7 king-move adjacent elements, with upper left element zero.

0, 2, 4, 13, 63, 264, 1005, 4113, 16720, 67541, 273173, 1105028, 4470455, 18086203, 73164414, 295979201, 1197372779, 4843899390, 19595676337, 79273069299, 320694228442, 1297348415225, 5248341466951, 21231835277428, 85892055453779

Offset

1,2

Comments

Column 3 of A298719.

Links

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

Formula

Empirical: a(n) = 3*a(n-1) +4*a(n-2) +3*a(n-3) -2*a(n-4) -18*a(n-5) -29*a(n-6) -32*a(n-7) +74*a(n-8) +74*a(n-9) -90*a(n-10) -73*a(n-11) +33*a(n-12) -21*a(n-13) -29*a(n-14) +32*a(n-15) +4*a(n-16) +4*a(n-17) +8*a(n-18)

Example

Some solutions for n=7
..0..0..1. .0..0..1. .0..1..1. .0..0..0. .0..0..0. .0..0..0. .0..0..0
..0..1..1. .0..1..1. .0..0..1. .1..0..0. .0..1..0. .1..0..1. .1..0..1
..0..0..0. .0..0..0. .1..1..1. .1..1..1. .1..1..1. .1..1..1. .1..1..1
..0..0..0. .0..0..0. .1..1..1. .1..1..1. .1..1..1. .1..1..1. .1..1..1
..0..1..0. .0..1..0. .1..0..1. .1..0..1. .1..0..1. .1..0..0. .0..0..1
..1..0..1. .1..1..0. .1..0..0. .1..0..0. .1..0..0. .0..0..1. .0..1..1
..1..1..1. .1..0..0. .1..1..0. .1..1..0. .1..1..0. .0..1..1. .0..0..1

Crossrefs

Cf. A298719.

Sequence in context: A298128 A132786 A298065 * A306445 A216670 A103845

Adjacent sequences: A298711 A298712 A298713 * A298715 A298716 A298717

Keyword

nonn

Author

R. H. Hardin, Jan 25 2018

Status

approved