A302965 T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 1, 2, 3 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
1, 2, 2, 4, 8, 4, 8, 29, 32, 8, 16, 105, 154, 128, 16, 32, 384, 786, 833, 512, 32, 64, 1405, 3924, 6206, 4527, 2048, 64, 128, 5135, 19868, 43588, 49521, 24602, 8192, 128, 256, 18766, 100161, 314989, 493132, 395493, 133757, 32768, 256, 512, 68589, 505908
Offset: 1
Examples
Some solutions for n=5 k=4 ..0..1..0..1. .0..1..1..0. .0..0..0..1. .0..0..1..0. .0..0..1..0 ..1..1..0..0. .0..0..0..0. .0..0..1..1. .1..0..1..1. .1..0..1..0 ..0..1..0..0. .1..1..1..1. .1..0..1..1. .0..1..0..0. .1..0..1..0 ..1..1..1..1. .1..0..0..1. .1..0..1..0. .0..1..0..0. .1..0..1..1 ..1..0..0..0. .1..0..1..0. .1..0..1..0. .0..1..0..1. .0..1..0..0
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) = 7*a(n-1) -7*a(n-2) -56*a(n-4) +64*a(n-5) for n>6
k=4: [order 19] for n>20
k=5: [order 80] for n>81
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 12] for n>13
n=4: [order 44] for n>45
Comments