%I #5 Mar 31 2012 12:35:50
%S 1,4,4,12,36,12,36,144,144,36,108,576,432,576,108,324,2304,1296,1296,
%T 2304,324,972,9216,3888,3600,3888,9216,972,2916,36864,11664,9216,9216,
%U 11664,36864,2916,8748,147456,34992,24336,24192,24336,34992,147456,8748
%N T(n,k)=One quarter the number of nXk 1..4 arrays with no two neighbors of any element equal to each other
%C Table starts
%C .....1.......4.....12......36.....108.....324.....972.....2916.....8748
%C .....4......36....144.....576....2304....9216...36864...147456...589824
%C ....12.....144....432....1296....3888...11664...34992...104976...314928
%C ....36.....576...1296....3600....9216...24336...63504...166464...435600
%C ...108....2304...3888....9216...24192...57600..137088...331776...802944
%C ...324....9216..11664...24336...57600..147456..331776...746496..1679616
%C ...972...36864..34992...63504..137088..331776..829440..1806336..3852288
%C ..2916..147456.104976..166464..331776..746496.1806336..4460544..9437184
%C ..8748..589824.314928..435600..802944.1679616.3852288..9437184.23003136
%C .26244.2359296.944784.1140624.1937664.3873024.8294400.19501056.47775744
%H R. H. Hardin, <a href="/A183362/b183362.txt">Table of n, a(n) for n = 1..335</a>
%e Some solutions for 6X5 with a(1,1)=1
%e ..1..1..3..2..2....1..1..3..2..1....1..1..4..2..3....1..1..3..2..4
%e ..4..4..3..1..1....2..2..4..4..3....3..3..4..1..3....4..4..3..1..1
%e ..3..2..2..4..4....4..3..1..1..3....4..2..2..1..4....3..2..2..4..3
%e ..3..1..1..3..2....4..3..2..2..4....4..1..3..3..4....3..1..1..4..3
%e ..2..4..4..3..1....1..1..4..3..1....3..1..4..2..2....2..4..3..2..2
%e ..1..3..2..2..1....2..2..4..3..1....3..2..4..1..3....1..4..3..1..4
%Y Column 1 is A003946(n-1)
%K nonn,tabl
%O 1,2
%A _R. H. Hardin_ Jan 04 2011
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