A298489 Number of nX3 0..1 arrays with every element equal to 0, 1, 2, 4 or 7 king-move adjacent elements, with upper left element zero.

4, 13, 20, 27, 43, 70, 106, 169, 276, 444, 720, 1183, 1947, 3207, 5311, 8826, 14681, 24474, 40897, 68419, 114596, 192212, 322715, 542258, 911962, 1534860, 2584781, 4355511, 7343271, 12386305, 20901774, 35285703, 59589460, 100666009, 170109263

Offset

1,1

Comments

Column 3 of A298494.

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) +3*a(n-3) -9*a(n-4) +4*a(n-5) -a(n-6) +9*a(n-7) -3*a(n-8) -a(n-9) -4*a(n-10) +2*a(n-11) for n>12

Example

Some solutions for n=9
..0..0..0. .0..1..0. .0..1..0. .0..1..1. .0..1..0. .0..1..0. .0..0..0
..1..1..1. .1..1..0. .1..0..1. .0..1..0. .1..0..0. .1..1..0. .1..1..1
..1..0..1. .1..1..0. .1..0..0. .1..0..1. .0..1..1. .1..1..0. .1..0..1
..1..1..1. .0..1..0. .1..0..0. .1..0..0. .1..0..1. .0..1..0. .1..1..1
..1..1..1. .1..0..1. .1..0..1. .1..0..0. .0..1..1. .1..1..0. .1..1..1
..1..0..1. .0..1..0. .0..0..1. .1..0..1. .1..0..0. .1..1..0. .1..0..1
..1..1..1. .1..0..1. .0..0..1. .0..1..0. .0..1..0. .0..1..0. .1..1..1
..0..0..0. .0..1..0. .1..0..1. .1..0..1. .1..0..0. .1..0..1. .0..0..0
..0..1..0. .0..1..1. .0..0..1. .1..0..0. .0..1..1. .0..1..0. .1..1..1

Crossrefs

Cf. A298494.

Sequence in context: A066993 A297884 A298289 * A299182 A030744 A173512

Adjacent sequences: A298486 A298487 A298488 * A298490 A298491 A298492

Keyword

nonn

Author

R. H. Hardin, Jan 20 2018

Status

approved