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%I #5 Mar 31 2012 12:36:28
%S 2,6,6,16,78,16,61,1015,1015,61,212,13526,50831,13526,212,753,181032,
%T 2548972,2548972,181032,753,2661,2421376,127561432,478107878,
%U 127561432,2421376,2661,9415,32393085,6385146382,89735942231,89735942231
%N T(n,k)=Half the number of nXk 0..3 arrays with no element equal to the average of its horizontal and vertical neighbors
%C Table starts
%C ......2...........6..............16.................61..................212
%C ......6..........78............1015..............13526...............181032
%C .....16........1015...........50831............2548972............127561432
%C .....61.......13526.........2548972..........478107878..........89735942231
%C ....212......181032.......127561432........89735942231.......63216096026066
%C ....753.....2421376......6385146382.....16851142959473....44545247280268585
%C ...2661....32393085....319626874708...3164557733113615.31390101087203449414
%C ...9415...433365018..15999836095846.594285270687803282
%C ..33302..5797636941.800916441358294
%C .117802.77561969587
%H R. H. Hardin, <a href="/A197109/b197109.txt">Table of n, a(n) for n = 1..71</a>
%e Some solutions for 6X6
%e ..1..0..0..0....1..0..0..0....1..0..0..0....1..0..0..0....1..0..0..0
%e ..0..0..2..1....0..0..2..1....0..0..2..1....0..0..2..1....0..0..2..1
%e ..0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0
%e ..2..3..0..0....2..1..0..0....2..1..0..0....2..2..0..0....2..1..0..0
%e ..2..2..1..1....3..0..2..3....0..3..0..3....3..0..3..3....0..0..1..3
%e ..1..3..3..1....0..2..2..1....1..1..0..1....2..0..0..1....3..3..2..3
%K nonn,tabl
%O 1,1
%A _R. H. Hardin_ Oct 10 2011