A279742 Number of 2 X n 0..1 arrays with no element equal to a strict majority of its horizontal and antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.

0, 2, 6, 14, 26, 48, 84, 146, 250, 426, 722, 1220, 2056, 3458, 5806, 9734, 16298, 27256, 45532, 75986, 126690, 211042, 351266, 584204, 970896, 1612418, 2676054, 4438526, 7357370, 12188736, 20181732, 33398930, 55244746, 91336218, 150937586

Offset

1,2

Links

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

Formula

Empirical: a(n) = 3*a(n-1) - a(n-2) - 3*a(n-3) + a(n-4) + a(n-5).

Empirical g.f.: 2*x^2*(1 - x^2 - 2*x^3) / ((1 - x)*(1 - x - x^2)^2). - Colin Barker, Feb 11 2019

Example

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

Crossrefs

Row 2 of A279741.

Sequence in context: A162716 A138318 A212964 * A068042 A068041 A182155

Adjacent sequences: A279739 A279740 A279741 * A279743 A279744 A279745

Keyword

nonn

Author

R. H. Hardin, Dec 18 2016

Status

approved