A267662 Number of nX3 0..1 arrays with every repeated value in every row unequal to the previous repeated value, and in every column equal to the previous repeated value, and new values introduced in row-major sequential order.
3, 18, 108, 453, 1800, 6654, 23967, 84552, 295176, 1023321, 3533484, 12170886, 41859891, 143844024, 494032074, 1696231551, 5822855280, 19986766938, 68599945065, 235446171408, 808076493654, 2773384864119, 9518456958738
Offset: 1
Keywords
Examples
Some solutions for n=8 ..0..0..1....0..1..0....0..1..1....0..0..1....0..0..1....0..0..1....0..1..1 ..1..0..0....1..0..1....1..0..1....1..1..0....0..1..0....0..1..0....0..0..1 ..0..1..0....1..1..0....0..1..0....0..1..0....1..1..0....0..0..1....0..1..0 ..1..0..1....1..0..0....1..0..1....1..0..0....0..0..1....1..1..0....1..0..1 ..1..0..0....1..1..0....1..0..0....0..1..0....0..1..0....0..1..0....0..1..0 ..1..1..0....1..0..1....1..0..1....0..1..0....1..0..0....0..0..1....1..0..1 ..1..0..0....1..1..0....0..1..1....0..1..0....0..1..0....0..1..0....0..1..0 ..1..0..1....1..0..1....1..0..0....0..1..1....1..0..1....0..1..1....1..0..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A267667.
Formula
Empirical: a(n) = 8*a(n-1) -13*a(n-2) -44*a(n-3) +135*a(n-4) +39*a(n-5) -375*a(n-6) +84*a(n-7) +461*a(n-8) -139*a(n-9) -294*a(n-10) +69*a(n-11) +98*a(n-12) -14*a(n-13) -16*a(n-14) +a(n-15) +a(n-16)
Comments