A280859 T(n,k)=Number of nXk 0..2 arrays with no element equal to more than one of its king-move neighbors and with new values introduced in order 0 sequentially upwards.
1, 2, 2, 4, 9, 4, 11, 29, 29, 11, 30, 110, 46, 110, 30, 82, 442, 96, 96, 442, 82, 224, 1708, 256, 124, 256, 1708, 224, 612, 6596, 678, 216, 216, 678, 6596, 612, 1672, 25624, 1698, 462, 282, 462, 1698, 25624, 1672, 4568, 99432, 4358, 1005, 491, 491, 1005, 4358
Offset: 1
Examples
Some solutions for n=4 k=4 ..0..1..1..2. .0..1..0..0. .0..1..2..2. .0..0..1..1. .0..0..1..0 ..2..2..0..2. .0..2..2..1. .0..1..0..1. .1..2..2..0. .1..2..1..2 ..0..1..0..1. .1..1..0..1. .2..2..0..2. .1..0..1..0. .0..2..0..2 ..2..1..2..2. .2..0..2..2. .0..1..1..2. .2..2..1..2. .0..1..0..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..480
Crossrefs
Column 1 is A021006(n-3).
Formula
Empirical for column k:
k=1: a(n) = 2*a(n-1) +2*a(n-2) for n>4
k=2: a(n) = 4*a(n-1) -2*a(n-2) +8*a(n-3) -8*a(n-4) for n>5
k=3: a(n) = 2*a(n-1) +4*a(n-3) -a(n-4) +2*a(n-6) -2*a(n-7) for n>9
k=4: [order 12] for n>16
k=5: [order 12] for n>18
k=6: [order 16] for n>22
k=7: [order 23] for n>29
Comments