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A181261
Number of (n+2)X9 binary matrices with every 3X3 block having exactly four 1's
2
61398, 74784, 91122, 112500, 162882, 242784, 386406, 750312, 1548594, 3449484, 8634042, 22315320, 59561118, 166095504, 468837162, 1339623540, 3893978322, 11377279584, 33414823926, 98854539192, 293124225474, 871179943644
OFFSET
1,1
COMMENTS
Column 7 of A181262
LINKS
EXAMPLE
Some solutions for 3X9
..0..0..1..0..0..1..0..0..1....0..0..0..1..0..0..0..0..1
..1..1..1..1..1..1..1..0..1....0..0..1..0..0..1..0..1..0
..0..0..0..0..0..0..0..1..0....1..1..1..0..1..1..1..0..1
CROSSREFS
Sequence in context: A215599 A330508 A204395 * A237013 A340438 A253613
KEYWORD
nonn
AUTHOR
R. H. Hardin Oct 10 2010
STATUS
approved