A279129 Number of nX3 0..1 arrays with no element equal to a strict majority of its horizontal and vertical neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

0, 9, 66, 256, 820, 2551, 7491, 21131, 57971, 155551, 409876, 1064002, 2727560, 6917391, 17381168, 43320628, 107203164, 263611545, 644549767, 1567944409, 3796630655, 9154650571, 21989697066, 52634342562, 125577952504, 298716701553

Offset

1,2

Comments

Column 3 of A279134.

Links

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

Formula

Empirical: a(n) = 6*a(n-1) -11*a(n-2) +5*a(n-3) +a(n-5) +9*a(n-6) -6*a(n-7) +3*a(n-8) -5*a(n-9) -a(n-11) for n>17

Example

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

Crossrefs

Cf. A279134.

Sequence in context: A152581 A122733 A118465 * A051375 A081902 A002695

Adjacent sequences: A279126 A279127 A279128 * A279130 A279131 A279132

Keyword

nonn

Author

R. H. Hardin, Dec 06 2016

Status

approved