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A207431
Number of 7Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 1 and 0 1 0 vertically
1
31, 961, 11067, 127449, 2048823, 32936121, 474552171, 6837470721, 102807481767, 1545802349809, 22864149458035, 338186399124025, 5035128104126565, 74966098845588129, 1113208750837622133, 16530588386278151641
OFFSET
1,1
COMMENTS
Row 7 of A207426
LINKS
EXAMPLE
Some solutions for n=4
..1..1..0..0....0..0..1..1....1..0..1..1....1..0..1..1....0..1..1..1
..0..0..1..1....0..1..1..1....0..1..1..0....1..1..0..1....1..1..0..1
..0..1..1..1....0..1..1..0....1..1..0..0....1..1..0..1....1..1..1..0
..0..1..1..0....0..0..1..1....1..1..0..0....1..0..0..1....0..1..1..0
..0..1..1..1....0..0..1..1....1..1..0..0....1..0..0..1....0..1..1..0
..0..0..1..1....0..0..1..1....1..1..0..0....1..0..0..1....0..1..1..0
..0..1..1..0....0..0..1..1....1..1..0..0....1..0..0..1....0..1..1..0
CROSSREFS
Sequence in context: A207247 A208168 A207441 * A208373 A171305 A009975
KEYWORD
nonn
AUTHOR
R. H. Hardin Feb 17 2012
STATUS
approved