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A187720
Number of (n+1)X(n+1) binary arrays with no 2X2 subblock commuting with any of its horizontal and vertical 2X2 subblock neighbors
0
16, 174, 3698, 161571, 13555195, 2287444987, 755272970945, 491415809239410, 627561470269866658, 1574769693877593164368
OFFSET
1,1
COMMENTS
Diagonal of A187729
EXAMPLE
Some solutions for 3X3
..0..0..1....1..0..1....1..0..1....0..1..1....1..1..1....1..0..0....1..1..1
..1..1..1....1..1..0....1..1..0....0..1..0....0..0..1....1..0..1....0..1..0
..0..1..0....1..1..0....1..1..1....1..1..1....1..0..1....1..1..0....1..0..0
CROSSREFS
Sequence in context: A021374 A253343 A215687 * A017931 A021129 A268869
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 13 2011
STATUS
approved