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%I #8 Jan 17 2019 17:20:44
%S 7,35,174,849,4083,19416,91491,427863,1988142,9187653,42256599,
%T 193542240,883204143,4017241083,18219040206,82410172617,371879874987,
%U 1674499435176,7525052043819,33755742643791,151168877259918,675941817039645
%N Number of n X 3 binary arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two not more than once.
%H R. H. Hardin, <a href="/A268990/b268990.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 10*a(n-1) - 31*a(n-2) + 30*a(n-3) - 9*a(n-4).
%F Empirical g.f.: x*(7 - 35*x + 41*x^2 - 16*x^3) / (1 - 5*x + 3*x^2)^2. - _Colin Barker_, Jan 17 2019
%e Some solutions for n=4:
%e ..1..1..0. .0..0..1. .0..0..1. .0..0..0. .1..1..0. .0..1..0. .1..0..0
%e ..0..1..0. .1..0..0. .1..0..0. .0..0..1. .0..0..0. .0..0..1. .1..0..0
%e ..0..0..0. .0..0..1. .1..0..0. .0..0..0. .0..0..1. .1..0..0. .1..1..0
%e ..1..0..1. .0..0..1. .0..1..1. .0..1..0. .0..0..1. .0..1..1. .0..1..0
%Y Column 3 of A268995.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 17 2016
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