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%I #6 Mar 02 2023 12:41:51
%S 48,2080,221696,23896064,2647261184,294517735424,32835998056448,
%T 3662495243829248,408547159030366208,45573786789742641152,
%U 5083813692357704941568,567106285442412421578752
%N Number of 4 X n 0..5 arrays with no element x(i,j) adjacent to itself or value 5-x(i,j) horizontally or antidiagonally, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order (unlabelled 6-colorings with no clashing color pairs).
%C Row 4 of A233256.
%H R. H. Hardin, <a href="/A233259/b233259.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 160*a(n-1) -6144*a(n-2) +86016*a(n-3) -393216*a(n-4) for n>8.
%e Some solutions for n=3
%e ..0..1..2....0..1..2....0..1..2....0..1..0....0..1..2....0..1..0....0..1..0
%e ..2..1..0....0..4..3....0..4..0....0..2..4....2..4..3....2..1..3....5..2..1
%e ..5..2..5....0..1..0....0..1..5....4..3..1....2..0..4....2..5..3....4..3..1
%e ..0..2..1....2..1..5....0..3..1....4..5..4....3..0..4....2..1..5....4..2..5
%Y Cf. A233256.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 06 2013