A281716 Number of 2 X n 0..1 arrays with no element unequal to a strict majority of its horizontal, diagonal and antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.

2, 3, 7, 14, 29, 61, 126, 265, 553, 1162, 2441, 5141, 10846, 22921, 48529, 102914, 218617, 465133, 991158, 2115193, 4520361, 9673530, 20728009, 44469637, 95515790, 205383337, 442086081, 952519602, 2054191833, 4433875101, 9578060710

Offset: 1

Author

R. H. Hardin, Jan 28 2017

Keywords

• nonn

Examples

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

Links

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

Crossrefs

Row 2 of A281715.

Formula

Empirical: a(n) = 3*a(n-1) + a(n-2) - 6*a(n-3) - 2*a(n-4) + 4*a(n-5).

Empirical g.f.: x*(2 - 3*x - 4*x^2 + 2*x^3 + 2*x^4) / ((1 - 2*x)*(1 - x - 3*x^2 + 2*x^4)). - Colin Barker, Feb 20 2019