%I #7 Mar 27 2023 15:36:49
%S 187,622645,2060918000,6852264918471,22781978610167987,
%T 75743730886453371522,251826890612151285556718,
%U 837254535307721417534184492,2783639010978210077196779661724
%N Number of n X 6 0..3 arrays with values 0..3 introduced in row major order and each element equal to no more than two horizontal and vertical neighbors.
%C Column 6 of A200801.
%H R. H. Hardin, <a href="/A200799/b200799.txt">Table of n, a(n) for n = 1..28</a>
%e Some solutions for n=3
%e ..0..1..0..0..2..1....0..1..0..2..2..2....0..1..0..0..0..0....0..1..0..1..2..3
%e ..1..0..0..1..2..2....1..0..0..3..1..3....1..0..0..2..1..0....1..0..0..2..3..3
%e ..0..0..1..2..3..2....0..0..1..2..0..2....0..0..1..2..2..2....0..0..1..0..1..2
%Y Cf. A200801.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 22 2011
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