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A220457
Equals one maps: number of n X 3 binary arrays indicating the locations of corresponding elements equal to exactly one of their horizontal, vertical and antidiagonal neighbors in a random 0..1 n X 3 array.
1
4, 22, 108, 691, 3872, 20897, 112582, 605780, 3249132, 17400206, 93125105, 498148634, 2663790130, 14241169579, 76125716517, 406890173406, 2174685548474, 11622471918192, 62113961444133, 331949857443568, 1773988622548460
OFFSET
1,1
COMMENTS
Column 3 of A220461.
LINKS
EXAMPLE
Some solutions for n=3
..1..1..1....0..0..0....0..0..0....1..0..0....1..1..1....0..0..0....1..0..1
..0..0..1....0..0..0....1..1..0....1..0..1....0..0..1....0..0..1....1..0..1
..0..1..1....0..0..1....1..1..0....0..0..1....1..0..1....0..1..0....1..0..1
CROSSREFS
Cf. A220461.
Sequence in context: A001436 A224243 A024420 * A108840 A007994 A006651
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 15 2012
STATUS
approved