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A221261
Number of 7Xn arrays of occupancy after each element moves to some horizontal or antidiagonal neighbor, with no occupancy greater than 2
0
0, 4096, 5822, 1250753956, 278802326676, 1080371161000000, 720107530988047980, 1273696206975009956961, 1220346471047321694829098
OFFSET
1,2
COMMENTS
Row 7 of A221255
EXAMPLE
Some solutions for n=3
..1..2..0....0..2..2....0..2..0....1..2..0....1..2..0....0..2..0....1..2..0
..1..2..0....0..2..0....1..2..0....0..2..0....0..2..1....1..2..0....0..2..0
..0..2..2....0..2..1....2..2..0....1..2..1....0..2..1....1..2..1....1..2..1
..0..2..0....0..2..0....0..2..0....0..2..0....0..2..0....1..2..1....0..2..0
..0..2..1....2..2..0....1..2..1....2..2..0....1..2..2....0..2..1....1..2..0
..0..2..2....0..2..1....1..2..1....0..2..1....0..2..1....0..2..0....1..2..1
..0..2..0....0..2..1....0..2..0....0..2..1....0..2..0....1..2..0....1..2..0
CROSSREFS
Sequence in context: A186490 A223694 A186489 * A069273 A043424 A138174
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 06 2013
STATUS
approved