|
%I #8 Feb 22 2019 05:49:43
%S 4,16,61,233,896,3444,13225,50789,195076,749256,2877717,11052673,
%T 42450984,163045180,626221537,2405182717,9237791852,35480380112,
%U 136272540429,523393640665,2010242874320,7720912327300,29654370583449
%N Number of 2 X n 0..1 arrays with no 1 equal to more than three of its horizontal, diagonal and antidiagonal neighbors.
%H R. H. Hardin, <a href="/A283858/b283858.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) + a(n-2) + 7*a(n-3) + 6*a(n-4).
%F Empirical g.f.: x*(4 + 4*x + 9*x^2 + 6*x^3) / (1 - 3*x - x^2 - 7*x^3 - 6*x^4). - _Colin Barker_, Feb 22 2019
%e Some solutions for n=4:
%e ..0..0..1..0. .1..0..0..0. .0..0..0..1. .0..1..1..0. .1..1..1..0
%e ..1..0..0..1. .1..1..1..1. .1..0..0..1. .0..1..0..1. .1..1..0..1
%Y Row 2 of A283857.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 17 2017
|
