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A278189 Number of 2 X n 0..3 arrays with every element plus 1 mod 4 equal to some element at offset (-1,-1) (-1,0) (-1,1) (0,-1) (0,1) or (1,0), with upper left element zero.

%I A278189 #7 Feb 08 2019 12:32:07
%S A278189 0,3,19,136,935,6381,43478,296105,2016307,13729364,93484479,636542307,
%T A278189 4334257038,29512224731,200950553535,1368284654492,9316734157423,
%U A278189 63438214373401,431954692843542,2941205998493005,20026852048660187
%N A278189 Number of 2 X n 0..3 arrays with every element plus 1 mod 4 equal to some element at offset (-1,-1) (-1,0) (-1,1) (0,-1) (0,1) or (1,0), with upper left element zero.
%H A278189 R. H. Hardin, <a href="/A278189/b278189.txt">Table of n, a(n) for n = 1..210</a>
%F A278189 Empirical: a(n) = 9*a(n-1) - 16*a(n-2) + 9*a(n-3) - 12*a(n-4) + 5*a(n-5) + 7*a(n-6) - 4*a(n-7).
%F A278189 Empirical g.f.: x^2*(3 - 2*x)*(1 - x + x^2)^2 / (1 - 9*x + 16*x^2 - 9*x^3 + 12*x^4 - 5*x^5 - 7*x^6 + 4*x^7). - _Colin Barker_, Feb 08 2019
%e A278189 Some solutions for n=4:
%e A278189 ..0..1..2..3. .0..2..3..2. .0..2..1..0. .0..1..2..1. .0..1..0..2
%e A278189 ..3..2..1..0. .1..1..0..2. .1..3..2..1. .3..1..3..0. .1..2..3..3
%Y A278189 Row 2 of A278188.
%K A278189 nonn
%O A278189 1,2
%A A278189 _R. H. Hardin_, Nov 14 2016