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T(n,k)=Number of nXk 0..2 arrays with every 0 next to a 1 and every 1 next to a 2 horizontally, vertically, diagonally or antidiagonally
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%I #4 Nov 24 2013 07:31:21

%S 1,3,3,7,51,7,15,381,381,15,33,3015,8227,3015,33,73,24651,187989,

%T 187989,24651,73,161,198945,4423815,12521603,4423815,198945,161,355,

%U 1607067,103104905,865692227,865692227,103104905,1607067,355,783,12991131

%N T(n,k)=Number of nXk 0..2 arrays with every 0 next to a 1 and every 1 next to a 2 horizontally, vertically, diagonally or antidiagonally

%C Table starts

%C ...1.......3..........7............15...............33...................73

%C ...3......51........381..........3015............24651...............198945

%C ...7.....381.......8227........187989..........4423815............103104905

%C ..15....3015.....187989......12521603........865692227..........59192688269

%C ..33...24651....4423815.....865692227.....176788379233.......35630507175345

%C ..73..198945..103104905...59192688269...35630507175345....21136983701111465

%C .161.1607067.2403848151.4047993038079.7183387830867849.12543745301001506913

%H R. H. Hardin, <a href="/A232459/b232459.txt">Table of n, a(n) for n = 1..180</a>

%F Empirical for column k:

%F k=1: a(n) = 2*a(n-1) +a(n-3)

%F k=2: a(n) = 6*a(n-1) +12*a(n-2) +39*a(n-3)

%F k=3: [order 9]

%F k=4: [order 15]

%F k=5: [order 46]

%e Some solutions for n=3 k=4

%e ..1..0..1..1....0..1..1..2....1..2..2..1....0..2..0..2....1..1..0..2

%e ..1..2..2..1....0..2..0..2....1..1..1..2....2..1..0..1....2..1..1..2

%e ..2..2..2..2....2..2..1..1....2..1..2..2....2..0..2..1....1..0..1..2

%Y Column 1 is A193641

%K nonn,tabl

%O 1,2

%A _R. H. Hardin_, Nov 24 2013