A241370 T(n,k)=Number of nXk 0..2 arrays with no element equal to fewer vertical neighbors than horizontal neighbors, with new values 0..2 introduced in row major order.
1, 1, 2, 2, 7, 5, 4, 28, 47, 14, 8, 121, 460, 326, 41, 16, 523, 4617, 7376, 2284, 122, 32, 2261, 46245, 169982, 118488, 16026, 365, 64, 9775, 463567, 3910194, 6280325, 1904096, 112458, 1094, 128, 42261, 4646421, 90008909, 332185927, 232173463
Offset: 1
Examples
Some solutions for n=4 k=4 ..0..1..0..1....0..1..0..2....0..1..0..2....0..1..0..2....0..1..0..2 ..1..1..2..0....1..0..2..1....0..2..0..0....2..0..0..1....0..1..2..1 ..1..2..2..0....2..0..0..1....1..2..0..0....1..0..2..0....2..0..1..0 ..1..2..2..1....0..1..0..2....0..1..0..1....2..0..1..2....1..0..1..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..144
Formula
Empirical for column k:
k=1: a(n) = 4*a(n-1) -3*a(n-2)
k=2: a(n) = 7*a(n-1) +2*a(n-3) -8*a(n-4) for n>5
k=3: [order 8]
k=4: [order 31]
k=5: [order 94]
Empirical for row n:
n=1: a(n) = 2*a(n-1) for n>2
n=2: a(n) = 5*a(n-1) -2*a(n-2) -4*a(n-3) for n>5
n=3: a(n) = 9*a(n-1) +16*a(n-2) -50*a(n-3) -72*a(n-4) -32*a(n-5) -32*a(n-6) for n>8
n=4: [order 21] for n>23
n=5: [order 65] for n>67
Comments