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%I #5 Mar 31 2012 12:37:07
%S 74,284,1074,4256,16986,68692,279504,1143842,4699050,19364230,
%T 79981548,330948764,1371291912,5688057508,23613366558,98091679448,
%U 407685449946,1695079113772,7050018583818,29329074681854,122037419381370
%N Number of 3X(n+1) 0..2 arrays with every 2X2 subblock having the same number of equal edges as its horizontal neighbors and a different number from its vertical neighbors, and new values 0..2 introduced in row major order
%C Row 2 of A205753
%H R. H. Hardin, <a href="/A205754/b205754.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 8*a(n-1) -2*a(n-2) -98*a(n-3) +73*a(n-4) +496*a(n-5) -196*a(n-6) -1120*a(n-7) -54*a(n-8) +813*a(n-9) +171*a(n-10) -90*a(n-11)
%e Some solutions for n=4
%e ..0..0..1..2..0....0..1..1..0..1....0..0..0..0..0....0..1..1..1..0
%e ..1..0..1..2..0....0..0..0..0..0....1..0..1..0..1....0..1..2..1..0
%e ..2..1..2..0..1....0..0..0..0..0....0..1..2..1..0....1..2..0..2..1
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 30 2012