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.
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
Keywords
Examples
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
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A267644.
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)
Comments