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%I #5 Mar 31 2012 12:35:59
%S 9113,13616,21473,38642,104312,336236,1348574,6736118,35668172,
%T 198726728,1153450280,6759631310,39967552418,238155498086,
%U 1421741546408,8502748040192,50935935695672,305257947824246,1830140712020354
%N 1/12 the number of (n+2)X6 0..2 arrays with each 3X3 subblock containing three of each value
%C Column 4 of A184386
%H R. H. Hardin, <a href="/A184381/b184381.txt">Table of n, a(n) for n = 1..74</a>
%F Empirical: a(n)=12*a(n-1)-47*a(n-2)+186*a(n-3)-1404*a(n-4)+5358*a(n-5)-12815*a(n-6)+59388*a(n-7)-216529*a(n-8)+421074*a(n-9)-1238292*a(n-10)+4200390*a(n-11)-7370532*a(n-12)+14448024*a(n-13)-43986924*a(n-14)+72896760*a(n-15)-99842544*a(n-16)+259089192*a(n-17)-414953280*a(n-18)+415059552*a(n-19)-848382336*a(n-20)+1329975936*a(n-21)-1013741568*a(n-22)+1425340800*a(n-23)-2203656192*a(n-24)+1333615104*a(n-25)-947303424*a(n-26)+1451188224*a(n-27)-725594112*a(n-28)
%e Some solutions with a(1,1)=0 for 4X6
%e ..0..2..2..0..1..2....0..1..2..0..1..2....0..2..2..1..2..2....0..1..0..0..1..2
%e ..1..1..0..1..2..0....1..0..2..2..0..2....1..0..1..0..2..1....0..2..2..0..1..0
%e ..1..0..2..1..0..2....2..0..1..1..0..1....1..2..0..1..0..0....2..1..1..2..2..1
%e ..2..2..0..2..1..0....1..2..0..1..2..0....0..2..2..1..2..2....0..1..0..0..1..2
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 12 2011