A281075 Number of nX3 0..1 arrays with no element equal to more than two of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.

0, 6, 55, 244, 894, 2948, 9188, 27580, 80579, 230740, 650623, 1812430, 4999598, 13680344, 37180126, 100464520, 270114217, 723090732, 1928306149, 5124900050, 13579351352, 35883161448, 94587730636, 248776803156, 652982317119

Offset

1,2

Comments

Column 3 of A281080.

Links

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

Formula

Empirical: a(n) = 8*a(n-1) -22*a(n-2) +18*a(n-3) +19*a(n-4) -28*a(n-5) -25*a(n-6) +46*a(n-7) +2*a(n-8) -24*a(n-9) -a(n-10) +12*a(n-11) -4*a(n-12) for n>16

Example

Some solutions for n=4
..0..1..1. .0..0..1. .0..1..1. .0..1..0. .0..1..0. .0..1..0. .0..1..1
..0..1..0. .1..1..0. .1..0..1. .0..1..1. .1..0..0. .1..1..0. .1..0..0
..0..1..0. .0..0..1. .1..1..0. .1..0..1. .1..1..1. .0..0..1. .1..0..1
..1..0..1. .1..0..1. .0..0..0. .0..0..1. .0..1..0. .1..0..1. .0..0..1

Crossrefs

Cf. A281080.

Sequence in context: A079465 A061792 A066514 * A009577 A097300 A295094

Adjacent sequences: A281072 A281073 A281074 * A281076 A281077 A281078

Keyword

nonn

Author

R. H. Hardin, Jan 14 2017

Status

approved