A281202 Number of n X 5 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.

5, 52, 176, 470, 1141, 2602, 5712, 12208, 25577, 52784, 107636, 217370, 435473, 866550, 1714460, 3375236, 6616061, 12919308, 25142632, 48783294, 94395997, 182209890, 350933080, 674521464, 1294078657, 2478473672, 4739410828

Offset: 1

Author

R. H. Hardin, Jan 17 2017

Keywords

• nonn

Examples

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

Links

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

Crossrefs

Column 5 of A281205.

Formula

Empirical: a(n) = 4*a(n-1) - 4*a(n-2) - 2*a(n-4) + 4*a(n-5) - a(n-8).

Empirical g.f.: x*(5 + 32*x - 12*x^2 - 26*x^3 - 25*x^4 + 2*x^5 + 12*x^6 + 4*x^7) / ((1 - x)^2*(1 - x - x^2 - x^3)^2). - Colin Barker, Feb 17 2019