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A281760 Number of n X 3 0..1 arrays with no element unequal to a strict majority of its horizontal, diagonal and antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.

%I A281760 #9 Feb 20 2019 06:09:22
%S A281760 2,14,47,90,201,374,672,1172,2015,3442,5859,9952,16876,28574,48309,
%T A281760 81554,137477,231418,389016,653080,1095019,1833842,3067719,5126372,
%U A281760 8557988,14273314,23784417,39600082,65880265,109518782,181933584,302025692
%N A281760 Number of n X 3 0..1 arrays with no element unequal to a strict majority of its horizontal, diagonal and antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.
%H A281760 R. H. Hardin, <a href="/A281760/b281760.txt">Table of n, a(n) for n = 1..210</a>
%F A281760 Empirical: a(n) = 4*a(n-1) - 4*a(n-2) - 2*a(n-3) + 4*a(n-4) - a(n-6) for n>11.
%F A281760 Empirical g.f.: x*(2 + 6*x - x^2 - 38*x^3 + 49*x^4 - 32*x^5 - 26*x^6 + 36*x^7 + 6*x^8 + 8*x^9 + 8*x^10) / ((1 - x)^2*(1 - x - x^2)^2). - _Colin Barker_, Feb 20 2019
%e A281760 Some solutions for n=4:
%e A281760 ..0..0..0. .0..0..0. .0..1..0. .0..0..0. .0..1..1. .0..0..0. .0..0..0
%e A281760 ..0..0..0. .0..0..0. .0..0..0. .0..0..1. .1..1..1. .0..0..0. .1..0..0
%e A281760 ..0..0..0. .0..0..0. .0..0..0. .0..0..0. .1..1..1. .0..1..0. .0..1..0
%e A281760 ..1..1..0. .0..1..1. .0..0..0. .1..1..1. .1..1..1. .1..0..0. .1..0..1
%Y A281760 Column 3 of A281765.
%K A281760 nonn
%O A281760 1,1
%A A281760 _R. H. Hardin_, Jan 29 2017