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A191481
Number of n X n symmetric binary matrices with each 1 adjacent to no more than 5 king-move neighboring 1s
1
2, 8, 57, 810, 22619, 1219719, 127845270, 26032342551, 10293291175885, 7905921432890001, 11794027077033857745, 34172420487154828030022, 192310322681418948575293174, 2102041102462630258932750207474
OFFSET
1,1
LINKS
EXAMPLE
Some solutions for n=4
..1..0..0..0....1..1..1..1....0..0..0..1....0..1..0..0....1..0..1..1
..0..0..0..0....1..0..1..0....0..1..0..1....1..0..0..1....0..0..0..1
..0..0..1..1....1..1..0..1....0..0..1..1....0..0..0..1....1..0..0..0
..0..0..1..0....1..0..1..0....1..1..1..0....0..1..1..0....1..1..0..0
CROSSREFS
Sequence in context: A153525 A153553 A334617 * A229529 A007347 A027257
KEYWORD
nonn
AUTHOR
R. H. Hardin Jun 03 2011
STATUS
approved