A300804 T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 1, 2, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
1, 2, 2, 4, 8, 4, 8, 32, 32, 8, 16, 128, 228, 128, 16, 32, 512, 1672, 1672, 512, 32, 64, 2048, 12228, 23096, 12228, 2048, 64, 128, 8192, 89472, 317504, 317504, 89472, 8192, 128, 256, 32768, 654628, 4369224, 8170504, 4369224, 654628, 32768, 256, 512, 131072
Offset: 1
Examples
Some solutions for n=5 k=4 ..0..0..0..1. .0..0..1..0. .0..0..0..0. .0..0..0..0. .0..0..1..0 ..1..0..1..1. .0..0..0..1. .1..1..0..0. .1..0..0..1. .0..1..1..0 ..1..0..0..1. .1..1..0..1. .1..1..1..0. .1..1..0..1. .1..0..0..1 ..0..0..1..1. .1..0..0..0. .0..0..1..0. .1..0..0..1. .1..1..0..0 ..1..0..1..1. .0..1..0..1. .0..0..1..1. .1..0..1..1. .0..0..1..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..312
Formula
Empirical for column k:
k=1: a(n) = 2*a(n-1)
k=2: a(n) = 4*a(n-1)
k=3: a(n) = 7*a(n-1) +3*a(n-2) -5*a(n-3)
k=4: [order 11]
k=5: [order 27] for n>29
k=6: [order 85] for n>87
Comments