A230184 T(n,k)=Number of nXk 0..2 arrays x(i,j) with each element horizontally or antidiagonally next to at least one element with value 2-x(i,j).
0, 3, 0, 3, 9, 0, 9, 27, 33, 0, 15, 159, 231, 129, 0, 33, 825, 3411, 1971, 513, 0, 63, 4395, 44487, 73857, 16815, 2049, 0, 129, 23307, 596973, 2432241, 1603431, 143451, 8193, 0, 255, 123729, 7957785, 82359177, 133265847, 34825803, 1223799, 32769, 0, 513
Offset: 1
Examples
Some solutions for n=3 k=4 ..2..0..1..1....0..2..1..1....2..0..0..1....0..2..2..0....1..1..2..2 ..0..2..2..0....0..0..2..2....0..2..1..1....0..1..2..0....2..0..0..0 ..0..2..1..1....1..1..0..2....1..1..0..2....1..2..0..2....0..2..2..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..238
Formula
Empirical for column k:
k=1: a(n) = a(n-1)
k=2: a(n) = 5*a(n-1) -4*a(n-2)
k=3: a(n) = 9*a(n-1) -4*a(n-2)
k=4: a(n) = 26*a(n-1) -97*a(n-2) +89*a(n-3) -18*a(n-4) +a(n-5)
k=5: [order 6] for n>8
k=6: [order 23] for n>24
k=7: [order 34] for n>37
Empirical for row n:
n=1: a(n) = a(n-1) +2*a(n-2)
n=2: a(n) = 4*a(n-1) +7*a(n-2) +a(n-3) -6*a(n-4) -5*a(n-5) for n>6
n=3: [order 21] for n>23
n=4: [order 93] for n>96
Comments