A302808 T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 1, 2, 3 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
1, 2, 2, 4, 8, 4, 8, 29, 32, 8, 16, 105, 169, 128, 16, 32, 384, 934, 1010, 512, 32, 64, 1405, 5117, 8718, 6084, 2048, 64, 128, 5135, 28128, 74072, 82367, 36456, 8192, 128, 256, 18766, 154494, 632004, 1089773, 773520, 218640, 32768, 256, 512, 68589, 848519
Offset: 1
Examples
Some solutions for n=5 k=4 ..0..1..0..0. .0..0..0..0. .0..0..1..0. .0..0..1..0. .0..1..1..0 ..1..0..1..1. .0..1..1..0. .1..0..1..0. .0..0..1..1. .1..1..1..1 ..1..0..1..0. .0..1..0..1. .1..0..1..1. .0..0..1..1. .0..0..0..0 ..0..1..0..1. .0..0..0..0. .1..0..0..0. .1..0..1..1. .0..1..1..0 ..1..1..0..0. .0..0..1..1. .1..0..1..0. .1..0..1..0. .1..1..1..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..180
Crossrefs
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) = 6*a(n-1) +24*a(n-3) -144*a(n-4) for n>6
k=4: [order 18] for n>20
k=5: [order 90] for n>92
Empirical for row n:
n=1: a(n) = 2*a(n-1)
n=2: a(n) = 3*a(n-1) +a(n-2) +4*a(n-3) +4*a(n-4)
n=3: [order 13] for n>15
n=4: [order 48] for n>50
Comments