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%I #8 Feb 28 2019 06:22:49
%S 4,13,37,126,385,1243,3924,12477,39625,125780,399527,1268481,4028320,
%T 12791471,40619227,128985178,409588149,1300636903,4130132236,
%U 13115120227,41646681705,132247843570,419949219621,1333536652989,4234607278278
%N Number of n X 4 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1 neighboring 1.
%H R. H. Hardin, <a href="/A297391/b297391.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + 6*a(n-2) + 4*a(n-3) - 3*a(n-4) - a(n-5) - 2*a(n-6) - a(n-7).
%F Empirical g.f.: x*(4 + 9*x - 5*x^3 - 3*x^4 - 3*x^5 - x^6) / (1 - x - 6*x^2 - 4*x^3 + 3*x^4 + x^5 + 2*x^6 + x^7). - _Colin Barker_, Feb 28 2019
%e Some solutions for n=5:
%e ..0..0..0..0. .0..0..1..1. .0..0..1..1. .0..1..0..0. .0..0..1..0
%e ..0..0..1..1. .0..0..0..0. .0..0..0..0. .1..0..0..0. .0..1..0..0
%e ..0..0..0..0. .0..0..0..0. .0..1..1..0. .0..0..0..0. .0..0..0..0
%e ..1..0..0..0. .0..1..0..0. .0..0..0..0. .0..0..1..1. .0..0..1..1
%e ..0..1..0..0. .1..0..0..0. .0..0..0..0. .0..0..0..0. .0..0..0..0
%Y Column 4 of A297395.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 29 2017
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