A301662 T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 1 or 4 horizontally or vertically adjacent elements, with upper left element zero.
1, 2, 2, 3, 3, 3, 5, 4, 4, 5, 8, 6, 6, 6, 8, 13, 9, 9, 9, 9, 13, 21, 14, 15, 13, 15, 14, 21, 34, 22, 26, 24, 24, 26, 22, 34, 55, 35, 46, 45, 46, 45, 46, 35, 55, 89, 56, 83, 89, 99, 99, 89, 83, 56, 89, 144, 90, 151, 182, 223, 254, 223, 182, 151, 90, 144, 233, 145, 276, 373, 528, 696
Offset: 1
Examples
Some solutions for n=5 k=4 ..0..0..1..0. .0..1..0..1. .0..1..0..1. .0..1..0..1. .0..1..0..1 ..1..1..0..1. .1..0..1..0. .1..1..1..0. .1..0..1..0. .1..0..1..0 ..0..0..1..0. .0..1..0..1. .0..1..0..1. .0..1..0..1. .0..1..1..1 ..1..1..0..1. .1..1..1..0. .1..0..0..0. .0..1..0..1. .1..0..1..0 ..0..0..1..0. .0..1..0..1. .0..1..0..1. .1..0..1..0. .0..1..0..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..544
Formula
Empirical for column k:
k=1: a(n) = a(n-1) +a(n-2)
k=2: a(n) = 2*a(n-1) -a(n-3)
k=3: a(n) = 2*a(n-1) -a(n-4)
k=4: a(n) = 2*a(n-1) +a(n-2) -a(n-3) -2*a(n-4) +a(n-5)
k=5: [order 11]
k=6: [order 18]
k=7: [order 31]
Comments