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

Author

R. H. Hardin, Dec 18 2016

Keywords

• nonn

Examples

			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
		

Links

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

Crossrefs

Row 2 of A279741.

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