%I #8 Apr 20 2018 05:46:25
%S 46583,6829,20152,79096,100600,108640,121144,148048,208576,364504,
%T 628144,1130851,1957270,3187537,5316589,8884561,14454997,24229909,
%U 40800838,67069960,112339666,188701339,310868899,519362947,870845683,1438553446
%N Number of (n+2) X 6 0..3 arrays with every 3 X 3 subblock commuting with each horizontal and vertical neighbor 3 X 3 subblock.
%C Column 4 of A186881.
%H R. H. Hardin, <a href="/A186876/b186876.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = 2*a(n-1) - a(n-2) + 3*a(n-3) - 6*a(n-4) + 3*a(n-5) + 3*a(n-6) - 3*a(n-7) for n>12.
%F Empirical g.f.: x*(46583 - 86337*x + 53077*x^2 - 94128*x^3 + 221571*x^4 - 172695*x^5 - 272148*x^6 + 245982*x^7 + 34047*x^8 - 94824*x^9 + 114075*x^11) / ((1 - x)*(1 - x - 3*x^3 + 3*x^4 - 3*x^6)). - _Colin Barker_, Apr 20 2018
%e Some solutions for 4 X 6:
%e ..0..1..0..0..0..0....0..0..0..0..0..1....0..0..0..0..0..3....0..0..0..0..2..0
%e ..0..0..1..0..0..0....0..0..0..0..0..0....0..0..0..0..0..1....0..0..0..0..0..0
%e ..3..0..0..1..0..0....0..0..0..0..0..0....3..0..0..0..0..0....1..0..0..0..0..0
%e ..0..3..0..0..1..0....2..2..0..0..0..0....1..0..0..0..0..0....1..1..0..0..0..2
%Y Cf. A186881.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 28 2011
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