A232376 T(n,k)=Number of nXk 0..3 arrays with every 0 next to a 1, every 1 next to a 2 and every 2 next to a 3 horizontally, diagonally or antidiagonally, and no adjacent values equal.
1, 2, 1, 4, 14, 1, 8, 74, 58, 1, 14, 296, 586, 230, 1, 26, 1130, 4404, 4550, 934, 1, 48, 4682, 32722, 63744, 36574, 3794, 1, 88, 19448, 259458, 927706, 957232, 292122, 15354, 1, 162, 79592, 2046700, 14326374, 27133338, 14297980, 2324142, 62266, 1, 298, 326810
Offset: 1
Examples
Some solutions for n=4 k=4 ..0..1..2..1....2..1..2..1....2..3..2..3....2..1..0..3....3..2..0..2 ..0..3..0..1....0..3..2..1....1..0..1..0....2..3..0..3....3..1..3..2 ..2..1..0..3....2..3..2..1....1..2..3..0....2..3..0..3....2..1..0..1 ..3..1..2..3....2..3..2..3....1..2..1..2....0..1..2..1....0..3..2..3
Links
- R. H. Hardin, Table of n, a(n) for n = 1..160
Crossrefs
Row 1 is A135491(n-1)
Formula
Empirical for column k:
k=1: a(n) = a(n-1)
k=2: a(n) = 2*a(n-1) +7*a(n-2) +6*a(n-3) -2*a(n-4) -3*a(n-5) +2*a(n-6) +a(n-7)
k=3: [order 15]
k=4: [order 22]
k=5: [order 64]
Empirical for row n:
n=1: a(n) = a(n-1) +a(n-2) +a(n-3) for n>4
n=2: [order 8] for n>9
n=3: [order 13] for n>14
n=4: [order 60] for n>61
Comments