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%I #4 Mar 11 2014 15:35:40
%S 17,208,5775,135766,3313304,80240064,1946535209,47203774762,
%T 1144788832875,27763021735024,673301630092412,16328724383102508,
%U 395999761775761841,9603677662310968264,232905759724044440751
%N Number of (4+1)X(n+1) 0..3 arrays with no element equal to all horizontal neighbors or unequal to all vertical neighbors, and new values 0..3 introduced in row major order
%C Row 4 of A239155
%H R. H. Hardin, <a href="/A239157/b239157.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 20*a(n-1) +125*a(n-2) -466*a(n-3) -1721*a(n-4) +3476*a(n-5) +3342*a(n-6) -3082*a(n-7) -5349*a(n-8) -4488*a(n-9) +8976*a(n-10) +2826*a(n-11) -2862*a(n-12) -324*a(n-13) +243*a(n-14)
%e Some solutions for n=4
%e ..0..1..1..2..3....0..1..2..0..3....0..1..0..0..1....0..1..0..2..0
%e ..0..1..1..2..3....0..1..2..0..3....0..1..0..0..1....0..1..0..2..0
%e ..0..1..0..1..3....0..1..0..0..3....0..1..0..0..1....0..1..0..1..3
%e ..0..2..0..1..3....2..0..0..2..3....1..2..0..3..0....3..0..3..1..3
%e ..0..2..0..1..3....2..0..0..2..3....1..2..0..3..0....3..0..3..1..3
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 11 2014