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T(n,k)=Number of nXk 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 4,2,0,1,3 for x=0,1,2,3,4
7

%I #5 Mar 31 2012 12:36:28

%S 1,1,1,2,7,2,3,20,20,3,5,65,120,65,5,8,203,698,698,203,8,13,648,4080,

%T 7407,4080,648,13,21,2057,24074,79785,79785,24074,2057,21,34,6527,

%U 141856,855746,1563352,855746,141856,6527,34,55,20740,833758,9248339,31096170

%N T(n,k)=Number of nXk 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 4,2,0,1,3 for x=0,1,2,3,4

%C Every 0 is next to 0 4's, every 1 is next to 1 2's, every 2 is next to 2 0's, every 3 is next to 3 1's, every 4 is next to 4 3's

%C Table starts

%C ..1.....1........2...........3.............5................8

%C ..1.....7.......20..........65...........203..............648

%C ..2....20......120.........698..........4080............24074

%C ..3....65......698........7407.........79785...........855746

%C ..5...203.....4080.......79785.......1563352.........31096170

%C ..8...648....24074......855746......31096170.......1146653592

%C .13..2057...141856.....9248339.....621506173......42346212260

%C .21..6527...833758....99900759...12367566377....1557004531014

%C .34.20740..4909544..1077578216..246209727883...57353100417462

%C .55.65833.28899922.11625151797.4904183446578.2112382332611192

%H R. H. Hardin, <a href="/A197047/b197047.txt">Table of n, a(n) for n = 1..144</a>

%e Some solutions for n=6 k=4

%e ..0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0

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

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

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

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

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

%Y Column 1 is A000045

%Y Column 2 is A196584

%K nonn,tabl

%O 1,4

%A _R. H. Hardin_ Oct 08 2011