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A200045
Number T(n,m) of ways of 4-coloring an n X m grid so that there is no rectangle with all 4 corners the same color.
3
4, 16, 252, 64, 3912, 228984, 256, 59928, 12870096, 2545607472, 1024, 906912, 696448224, 465659203104, 272454472598400, 4096, 13571712, 36376835616, 79102304162784, 140221913588582784
OFFSET
1,1
COMMENTS
The rectangles have sides parallel to the x- and y-axes.
EXAMPLE
Triangle starts:
4;
16, 252;
64, 3912, 228984;
256, 59928, 12870096, 2545607472;
1024, 906912, 696448224, 465659203104, 272454472598400;
...
CROSSREFS
KEYWORD
nonn,tabl,more
AUTHOR
Jason Davies, Nov 14 2011
EXTENSIONS
T(6,5) from Jason Davies, Nov 08 2012
STATUS
approved