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%I #7 Feb 28 2019 06:22:40
%S 1,9,19,37,127,323,763,2121,5557,14031,37065,97027,250371,653707,
%T 1706245,4431885,11544027,30085525,78290135,203852347,530958219,
%U 1382353401,3599332477,9373032927,24405570561,63547912011,165475162027,430875964651
%N Number of 3 X n 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1 neighboring 1.
%H R. H. Hardin, <a href="/A297396/b297396.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + a(n-2) + 8*a(n-3) + a(n-4) - 2*a(n-6).
%F Empirical g.f.: x*(1 + 8*x + 9*x^2 + x^3 - 2*x^4 - 2*x^5) / (1 - x - x^2 - 8*x^3 - x^4 + 2*x^6). - _Colin Barker_, Feb 28 2019
%e Some solutions for n=5:
%e ..0..0..0..1..1. .0..1..1..0..0. .0..0..0..1..0. .1..0..0..0..0
%e ..1..1..0..0..0. .0..0..0..0..0. .0..0..0..0..1. .0..1..0..0..0
%e ..0..0..0..1..1. .0..0..0..1..1. .0..0..0..0..0. .0..0..0..1..1
%Y Row 3 of A297395.
%K nonn
%O 1,2
%A _R. H. Hardin_, Dec 29 2017
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