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A278203 Number of n X 3 0..1 arrays with every element both equal and not equal to some elements at offset (-1,-1) (-1,0) (-1,1) (0,-1) (0,1) (1,-1) (1,0) or (1,1), with upper left element zero.

%I A278203 #8 Feb 09 2019 08:49:12
%S A278203 0,15,97,666,4827,34869,251260,1811189,13056663,94122538,678506791,
%T A278203 4891196693,35259493158,254177432493,1832305613593,13208662283862,
%U A278203 95218154664535,686405389318065,4948135785116200,35669952667919773
%N A278203 Number of n X 3 0..1 arrays with every element both equal and not equal to some elements at offset (-1,-1) (-1,0) (-1,1) (0,-1) (0,1) (1,-1) (1,0) or (1,1), with upper left element zero.
%H A278203 R. H. Hardin, <a href="/A278203/b278203.txt">Table of n, a(n) for n = 1..210</a>
%F A278203 Empirical: a(n) = 6*a(n-1) + 7*a(n-2) + 11*a(n-3) + 11*a(n-4) - 9*a(n-5) + 3*a(n-7) - 2*a(n-8) for n>9.
%F A278203 Empirical g.f.: x^2*(15 + 7*x - 21*x^2 - 13*x^3 + 13*x^4 - x^5 - 4*x^6 + 2*x^7) / (1 - 6*x - 7*x^2 - 11*x^3 - 11*x^4 + 9*x^5 - 3*x^7 + 2*x^8). - _Colin Barker_, Feb 09 2019
%e A278203 Some solutions for n=4:
%e A278203 ..0..0..0. .0..0..1. .0..1..0. .0..1..0. .0..0..0. .0..1..1. .0..0..1
%e A278203 ..0..1..1. .0..1..0. .1..0..0. .0..1..0. .1..1..0. .1..0..1. .1..0..1
%e A278203 ..0..1..0. .1..1..1. .0..0..0. .1..0..1. .1..0..0. .0..0..1. .0..1..0
%e A278203 ..0..0..1. .0..0..1. .0..1..1. .0..1..1. .0..1..1. .1..1..0. .0..1..0
%Y A278203 Column 3 of A278208.
%K A278203 nonn
%O A278203 1,2
%A A278203 _R. H. Hardin_, Nov 15 2016