A231940 T(n,k)=Number of nXk 0..3 arrays with no element less than a strict majority of its horizontal, diagonal and antidiagonal neighbors.
4, 4, 16, 16, 84, 64, 50, 668, 318, 256, 144, 5070, 8426, 1328, 1024, 422, 42104, 206808, 152180, 6064, 4096, 1268, 326010, 4736026, 11159202, 2462572, 26918, 16384, 3823, 2511252, 94464137, 691418144, 518972238, 36885538, 116909, 65536, 11472
Offset: 1
Examples
Some solutions for n=3 k=4 ..0..0..0..1....0..0..0..3....2..0..0..2....0..2..2..1....0..0..1..0 ..2..0..2..2....3..0..0..3....3..3..0..0....3..0..0..2....2..0..0..3 ..2..3..0..0....1..2..3..0....1..0..0..2....2..0..0..0....0..2..3..2
Links
- R. H. Hardin, Table of n, a(n) for n = 1..84
Formula
Empirical for column k:
k=1: a(n) = 4*a(n-1)
k=2: [order 19] for n>20
k=3: [order 65] for n>66
Empirical for row n:
n=1: a(n) = 4*a(n-1) -6*a(n-2) +10*a(n-3) -5*a(n-4) +6*a(n-5) -a(n-6) +a(n-7) for n>8
n=2: [order 15]
Comments