%I #4 Nov 08 2016 12:32:06
%S 0,30,410,6372,98410,1516632,23376048,360279838,5552721246,
%T 85579707940,1318971923980,20328262601458,313303293592114,
%U 4828693685579504,74420802953575212,1146988455048830360,17677617866311586368
%N Number of 3Xn 0..2 arrays with every element plus 1 mod 3 equal to some element at offset (-1,-1) (-1,0) (-1,1) (0,-1) (0,1) or (1,0), with upper left element zero.
%C Row 3 of A278014.
%H R. H. Hardin, <a href="/A278016/b278016.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 18*a(n-1) -32*a(n-2) -102*a(n-3) -406*a(n-4) +1452*a(n-5) +2596*a(n-6) +2458*a(n-7) -22648*a(n-8) -18454*a(n-9) +18879*a(n-10) +122984*a(n-11) -5236*a(n-12) -144156*a(n-13) -72858*a(n-14) +40286*a(n-15) +58052*a(n-16) +2232*a(n-17) -1856*a(n-18) -4224*a(n-19)
%e Some solutions for n=4
%e ..0..1..0..2. .0..2..0..2. .0..1..2..0. .0..1..2..1. .0..2..1..1
%e ..0..2..1..0. .1..0..1..2. .1..2..0..1. .0..2..0..1. .1..2..1..2
%e ..2..0..2..2. .0..2..1..0. .2..0..1..0. .1..1..2..2. .0..1..0..0
%Y Cf. A278014.
%K nonn
%O 1,2
%A _R. H. Hardin_, Nov 08 2016
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