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%I #5 Mar 31 2012 12:37:22
%S 2,15,100,868,7780,69988,629860,5668708,51018340,459165028,4132485220,
%T 37192366948,334731302500,3012581722468,27113235502180,
%U 244019119519588,2196172075676260,19765548681086308,177889938129776740
%N Number of nX2 0..3 arrays with new values 0..3 introduced in row major order and no element equal to any knight-move neighbor (colorings ignoring permutations of colors)
%C Column 2 of A208353
%H R. H. Hardin, <a href="/A208347/b208347.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 10*a(n-1) -9*a(n-2) for n>4
%e Some solutions for n=4
%e ..0..0....0..1....0..0....0..0....0..0....0..0....0..1....0..0....0..0....0..0
%e ..0..0....1..0....0..0....0..0....1..0....1..1....1..2....0..0....0..0....1..0
%e ..1..1....0..1....1..2....1..1....1..1....1..1....0..1....1..1....1..2....1..1
%e ..2..2....1..2....3..2....1..1....1..0....0..0....0..0....1..2....1..3....1..2
%K nonn
%O 1,1
%A _R. H. Hardin_ Feb 25 2012