A300472 T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 1, 2 or 3 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
1, 2, 2, 4, 8, 4, 8, 29, 29, 8, 16, 108, 160, 108, 16, 32, 401, 925, 925, 401, 32, 64, 1490, 5363, 8608, 5363, 1490, 64, 128, 5536, 31106, 80914, 80914, 31106, 5536, 128, 256, 20569, 180397, 759100, 1231578, 759100, 180397, 20569, 256, 512, 76424, 1046223
Offset: 1
Examples
Some solutions for n=5 k=4 ..0..0..1..0. .0..1..0..0. .0..0..1..0. .0..1..1..0. .0..1..0..0 ..1..0..1..1. .1..0..1..0. .0..1..0..0. .1..0..1..1. .0..0..1..1 ..1..0..1..1. .1..0..1..1. .0..0..1..1. .0..0..1..0. .1..1..0..0 ..1..0..0..0. .0..1..0..0. .1..1..0..1. .1..1..0..0. .0..1..0..1 ..0..1..1..0. .1..1..1..0. .0..0..1..1. .0..0..1..1. .0..0..1..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..264
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: a(n) = 6*a(n-1) -a(n-2) -a(n-3) +a(n-4) -4*a(n-5) +a(n-6) -a(n-7)
k=4: [order 22]
k=5: [order 58] for n>59
Comments