A304270 T(n,k)=Number of nXk 0..1 arrays with every element unequal to 0, 1, 5 or 8 king-move adjacent elements, with upper left element zero.
1, 2, 2, 3, 1, 3, 5, 3, 3, 5, 8, 5, 6, 5, 8, 13, 7, 10, 10, 7, 13, 21, 13, 19, 21, 19, 13, 21, 34, 23, 37, 50, 50, 37, 23, 34, 55, 37, 67, 116, 146, 116, 67, 37, 55, 89, 63, 124, 259, 404, 404, 259, 124, 63, 89, 144, 109, 235, 601, 1074, 1246, 1074, 601, 235, 109, 144, 233
Offset: 1
Examples
Some solutions for n=5 k=4 ..0..1..0..0. .0..0..0..0. .0..0..0..0. .0..0..1..0. .0..0..0..0 ..0..0..0..0. .1..0..0..1. .0..0..0..0. .0..0..0..0. .0..0..0..0 ..0..0..0..0. .0..0..0..0. .1..0..0..0. .0..0..0..0. .0..1..0..0 ..0..0..0..0. .0..0..0..0. .0..0..0..0. .0..0..0..0. .0..0..0..0 ..0..1..0..0. .0..0..0..0. .0..0..0..0. .0..0..1..0. .0..0..0..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..1012
Formula
Empirical for column k:
k=1: a(n) = a(n-1) +a(n-2)
k=2: a(n) = a(n-1) +2*a(n-3) for n>4
k=3: a(n) = a(n-1) +3*a(n-3) for n>4
k=4: a(n) = a(n-1) +a(n-2) +5*a(n-3) +a(n-4) -3*a(n-5) -3*a(n-6) for n>7
k=5: [order 9] for n>10
k=6: [order 12] for n>13
k=7: [order 24] for n>25
Comments