A298456 Number of nX3 0..1 arrays with every element equal to 2, 3, 4, 5 or 6 king-move adjacent elements, with upper left element zero.

0, 3, 8, 30, 153, 710, 3490, 17087, 84008, 413964, 2040233, 10061180, 49619258, 244733629, 1207118898, 5954066110, 29368423541, 144860206974, 714526449382, 3524421573945, 17384313721480, 85748656629026, 422957892588941

Offset

1,2

Comments

Column 3 of A298461.

Links

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

Formula

Empirical: a(n) = 4*a(n-1) +10*a(n-2) -19*a(n-3) -42*a(n-4) +17*a(n-5) +27*a(n-6) -39*a(n-7) +45*a(n-8) +75*a(n-9) -35*a(n-10) -6*a(n-11) +6*a(n-12) -8*a(n-13) for n>15

Example

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

Crossrefs

Cf. A298461.

Sequence in context: A078619 A274934 A066304 * A145776 A066165 A323775

Adjacent sequences: A298453 A298454 A298455 * A298457 A298458 A298459

Keyword

nonn

Author

R. H. Hardin, Jan 19 2018

Status

approved