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%I #7 Feb 26 2019 12:06:16
%S 7,66,497,3808,29212,223995,1717882,13174266,101033369,774822892,
%T 5942100272,45569854023,349474289622,2680111429330,20553721242845,
%U 157626080234992,1208831279237072,9270503076704855,71095304015354510
%N Number of n X 4 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 1 or 2 neighboring 1s.
%H R. H. Hardin, <a href="/A297310/b297310.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 4*a(n-1) + 26*a(n-2) + 22*a(n-3) - 43*a(n-4) - a(n-5) + 7*a(n-6) - a(n-7) - a(n-8) for n>9.
%F Empirical g.f.: x*(7 + 38*x + 51*x^2 - 50*x^3 - 93*x^4 + 50*x^5 + 2*x^6 - 10*x^7 + x^8) / ((1 - 7*x - 5*x^2 - x^3)*(1 + 3*x - 6*x^3 + 4*x^4 - x^5)). - _Colin Barker_, Feb 26 2019
%e Some solutions for n=5:
%e ..0..1..1..0. .1..1..0..1. .1..1..1..0. .0..1..1..0. .0..0..1..1
%e ..1..0..0..1. .0..0..1..1. .0..1..0..1. .1..1..0..0. .0..1..0..1
%e ..0..1..1..0. .0..0..1..1. .1..0..1..0. .0..1..0..0. .1..0..1..1
%e ..1..0..0..0. .0..0..0..0. .0..1..0..0. .1..0..1..0. .0..0..0..1
%e ..1..1..1..0. .0..1..1..0. .0..1..1..0. .1..1..0..0. .1..1..1..0
%Y Column 4 of A297314.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 28 2017
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