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A279460 Number of n X 2 0..1 arrays with no element equal to a strict majority of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.

%I A279460 #9 Feb 11 2019 05:20:04
%S A279460 0,2,6,20,66,210,658,2036,6236,18928,57032,170790,508748,1508462,
%T A279460 4454576,13107640,38446722,112448726,328044512,954771282,2772970950,
%U A279460 8038036642,23258558892,67190053760,193807573324,558249440024,1605908314802
%N A279460 Number of n X 2 0..1 arrays with no element equal to a strict majority of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.
%H A279460 R. H. Hardin, <a href="/A279460/b279460.txt">Table of n, a(n) for n = 1..210</a>
%F A279460 Empirical: a(n) = 4*a(n-1) - 2*a(n-2) - 3*a(n-4) - 14*a(n-5) - 14*a(n-6) - 14*a(n-7) - 13*a(n-8) - 6*a(n-9) - a(n-10).
%F A279460 Empirical g.f.: 2*x^2*(1 + x)*(1 - 2*x + 2*x^2 - 3*x^3 - x^4 - x^5 - x^6) / (1 - 2*x - x^2 - 2*x^3 - 3*x^4 - x^5)^2. - _Colin Barker_, Feb 11 2019
%e A279460 Some solutions for n=4:
%e A279460 ..0..1. .0..0. .0..1. .0..0. .0..1. .0..1. .0..1. .0..0. .0..0. .0..0
%e A279460 ..0..0. .1..0. .0..0. .1..1. .0..1. .1..0. .1..0. .1..0. .1..0. .1..0
%e A279460 ..1..0. .1..0. .0..1. .0..1. .0..1. .0..1. .1..0. .0..1. .0..1. .1..1
%e A279460 ..1..1. .1..0. .1..0. .0..0. .0..0. .0..0. .1..1. .0..1. .1..0. .0..0
%Y A279460 Column 2 of A279466.
%K A279460 nonn
%O A279460 1,2
%A A279460 _R. H. Hardin_, Dec 12 2016