A304342 Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 4 or 5 king-move adjacent elements, with upper left element zero.

4, 14, 27, 71, 225, 613, 1752, 5102, 14673, 42235, 122016, 352304, 1016793, 2936025, 8478588, 24482962, 70700917, 204172771, 589619638, 1702740928, 4917307073, 14200615673, 41009800440, 118431859204, 342018606381, 987713762163

Offset

1,1

Comments

Column 3 of A304347.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +3*a(n-2) +6*a(n-3) -11*a(n-4) -25*a(n-5) -27*a(n-6) +19*a(n-7) +61*a(n-8) +59*a(n-9) -39*a(n-11) -13*a(n-12) -14*a(n-13) -20*a(n-14) -24*a(n-15) for n>16

Example

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

Crossrefs

Cf. A304347.

Sequence in context: A175680 A094320 A200546 * A066907 A130439 A289179

Adjacent sequences: A304339 A304340 A304341 * A304343 A304344 A304345

Keyword

nonn

Author

R. H. Hardin, May 11 2018

Status

approved