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A267639
Number of nX3 0..1 arrays with every repeated value in every row and column unequal to the previous repeated value, and new values introduced in row-major sequential order.
1
3, 18, 51, 189, 429, 1353, 2829, 8427, 16899, 49443, 96657, 282717, 542913, 1601355, 3032535, 9058395, 16953333, 51380925, 95168013, 292791555, 537249507, 1677388467, 3051796161, 9662000493, 17443801617, 55944191787, 100303228599
OFFSET
1,1
COMMENTS
Column 3 of A267644.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +16*a(n-2) -33*a(n-3) -91*a(n-4) +198*a(n-5) +216*a(n-6) -523*a(n-7) -180*a(n-8) +576*a(n-9) -180*a(n-11)
EXAMPLE
Some solutions for n=6
..0..0..1....0..1..1....0..1..1....0..0..1....0..1..1....0..1..0....0..0..1
..0..0..1....1..0..0....0..1..1....0..1..1....1..0..1....0..0..1....0..1..1
..1..1..0....1..1..0....1..0..0....1..1..0....1..1..0....1..1..0....1..1..0
..1..0..1....0..1..1....0..0..1....1..0..1....0..0..1....0..1..1....1..0..0
..0..1..0....1..0..0....1..1..0....0..1..0....0..1..0....1..0..0....0..0..1
..1..0..0....0..1..1....1..0..1....1..0..0....1..0..1....0..1..1....1..1..0
CROSSREFS
Cf. A267644.
Sequence in context: A304976 A364599 A064043 * A238649 A375764 A268484
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 18 2016
STATUS
approved