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A279263 Number of n X 3 0..1 arrays with no element equal to a strict majority of its horizontal and vertical neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.

%I A279263 #7 Feb 10 2019 12:38:49
%S A279263 2,10,29,86,240,626,1603,4030,9973,24388,59068,141920,338689,803630,
%T A279263 1897359,4460226,10444904,24376990,56720671,131619998,304674313,
%U A279263 703690416,1621976820,3731637260,8570604669,19653441614,45002040707
%N A279263 Number of n X 3 0..1 arrays with no element equal to a strict majority of its horizontal and vertical neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.
%H A279263 R. H. Hardin, <a href="/A279263/b279263.txt">Table of n, a(n) for n = 1..210</a>
%F A279263 Empirical: a(n) = 4*a(n-1) - 4*a(n-2) + 2*a(n-3) - 4*a(n-4) - a(n-6) for n>9.
%F A279263 Empirical g.f.: x*(2 + 2*x - 3*x^2 + 6*x^3 - 8*x^5 + 5*x^6 - 4*x^7 + 2*x^8) / (1 - 2*x - x^3)^2. - _Colin Barker_, Feb 10 2019
%e A279263 Some solutions for n=4:
%e A279263 ..0..1..0. .0..1..0. .0..1..1. .0..0..1. .0..1..1. .0..1..0. .0..0..1
%e A279263 ..0..0..1. .1..0..1. .0..0..0. .0..1..0. .1..1..0. .1..0..0. .1..1..0
%e A279263 ..1..1..0. .0..1..1. .0..1..1. .1..0..1. .0..0..1. .0..0..1. .0..0..0
%e A279263 ..0..1..0. .1..0..0. .1..0..0. .0..1..0. .1..1..0. .1..1..0. .1..1..0
%Y A279263 Column 3 of A279268.
%K A279263 nonn
%O A279263 1,1
%A A279263 _R. H. Hardin_, Dec 08 2016