A301450 T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 1, 2, 3, 5 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
1, 2, 2, 4, 8, 4, 8, 29, 29, 8, 16, 108, 171, 108, 16, 32, 401, 1008, 1008, 401, 32, 64, 1490, 5930, 9541, 5930, 1490, 64, 128, 5536, 34976, 91370, 91370, 34976, 5536, 128, 256, 20569, 206266, 877044, 1423344, 877044, 206266, 20569, 256, 512, 76424, 1216562
Offset: 1
Examples
Some solutions for n=5 k=4 ..0..0..0..1. .0..1..1..1. .0..1..0..1. .0..1..1..1. .0..0..0..1 ..1..0..1..0. .0..1..0..0. .1..0..1..0. .1..0..0..0. .0..1..0..0 ..1..0..1..1. .1..0..0..0. .0..1..0..1. .1..0..1..1. .1..1..0..1 ..0..1..0..1. .1..1..0..1. .0..0..1..0. .1..0..1..0. .0..1..0..1 ..1..1..0..0. .1..1..0..1. .0..1..1..1. .1..0..0..1. .1..1..0..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..199
Formula
Empirical for column k:
k=1: a(n) = 2*a(n-1)
k=2: a(n) = 3*a(n-1) +3*a(n-2) -a(n-3) -a(n-4)
k=3: [order 13]
k=4: [order 40]
Comments