%I #6 Aug 12 2016 06:54:17
%S 0,6,36,906,31818,770406,28194516,857204082,29334686760,981701367120,
%T 33610273278060,1163386717573176,40538287466544630,
%U 1426710530475496692,50491865673413814126,1798794705043994212440,64408154737694955274872
%N Number of 4Xn arrays containing n copies of 0..4-1 with every element equal to at least one vertical or antidiagonal neighbor and the top left element equal to 0.
%C Row 4 of A268159.
%H R. H. Hardin, <a href="/A268161/b268161.txt">Table of n, a(n) for n = 1..20</a>
%e Some solutions for n=4
%e ..0..1..0..2....0..1..0..3....0..2..3..1....0..0..1..3....0..3..2..0
%e ..0..1..0..2....0..1..0..3....0..2..3..1....0..0..1..3....0..3..2..0
%e ..1..3..3..2....1..3..2..2....3..1..2..0....2..2..3..1....2..3..1..1
%e ..1..3..3..2....1..3..2..2....3..1..2..0....2..2..3..1....2..3..1..1
%Y Cf. A268159.
%K nonn
%O 1,2
%A _R. H. Hardin_, Jan 27 2016
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