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A191573
Number of n X n symmetric binary matrices with each 1 adjacent to no more than 5 knight-move neighboring 1s
0
2, 8, 64, 1024, 27243, 1382864, 140750620, 28217901400, 10950671730896, 8078548919508508, 11458732300832773022
OFFSET
1,1
EXAMPLE
Some solutions for n=6
..0..1..0..1..0..1....0..1..0..0..1..0....0..0..0..0..1..1....0..1..0..1..1..0
..1..0..0..1..0..0....1..0..0..0..0..1....0..0..0..0..0..1....1..0..0..0..0..0
..0..0..0..1..0..1....0..0..0..1..0..0....0..0..1..0..0..1....0..0..0..0..0..0
..1..1..1..0..0..1....0..0..1..1..0..0....0..0..0..1..1..0....1..0..0..1..0..0
..0..0..0..0..0..0....1..0..0..0..1..0....1..0..0..1..1..1....1..0..0..0..1..0
..1..0..1..1..0..1....0..1..0..0..0..0....1..1..1..0..1..1....0..0..0..0..0..0
CROSSREFS
Sequence in context: A153563 A178169 A191572 * A136283 A139680 A153544
KEYWORD
nonn
AUTHOR
R. H. Hardin Jun 06 2011
STATUS
approved