A240893 T(n,k)=Number of nXk 0..2 arrays with no element equal to a different number of vertical neighbors than horizontal neighbors, with new values 0..2 introduced in row major order.
1, 1, 1, 2, 4, 2, 4, 11, 11, 4, 8, 36, 57, 36, 8, 16, 116, 289, 289, 116, 16, 32, 376, 1485, 2362, 1485, 376, 32, 64, 1216, 7609, 19065, 19065, 7609, 1216, 64, 128, 3936, 38981, 154858, 245268, 154858, 38981, 3936, 128, 256, 12736, 199761, 1255585, 3146755
Offset: 1
Examples
Some solutions for n=4 k=4 ..0..1..2..1....0..1..2..0....0..1..1..0....0..1..2..1....0..1..2..0 ..1..2..1..0....2..0..0..1....2..1..1..2....2..0..1..2....1..2..0..2 ..2..1..0..2....1..0..0..2....1..0..0..1....1..2..0..1....0..0..2..1 ..1..2..1..0....2..1..2..0....2..0..0..2....0..1..2..0....0..0..1..2
Links
- R. H. Hardin, Table of n, a(n) for n = 1..180
Formula
Empirical for column k:
k=1: a(n) = 2*a(n-1) for n>2
k=2: a(n) = 2*a(n-1) +4*a(n-2) for n>4
k=3: a(n) = 3*a(n-1) +8*a(n-2) +14*a(n-3) +4*a(n-4)
k=4: [order 16]
k=5: [order 48]
Comments