A302670 T(n,k)=Number of nXk 0..1 arrays with every element equal to 1, 2, 3 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
0, 1, 0, 1, 3, 0, 2, 14, 11, 0, 3, 45, 43, 34, 0, 5, 146, 164, 194, 111, 0, 8, 537, 760, 934, 691, 361, 0, 13, 1934, 3425, 6110, 4267, 2802, 1172, 0, 21, 6861, 15569, 38736, 42367, 21949, 10660, 3809, 0, 34, 24386, 70323, 251254, 352174, 316977, 106793, 41839
Offset: 1
Examples
Some solutions for n=5 k=4 ..0..0..1..1. .0..0..1..1. .0..1..1..0. .0..1..1..1. .0..1..1..0 ..1..1..0..1. .0..1..0..0. .1..0..0..1. .0..0..1..1. .1..0..0..1 ..1..1..0..1. .1..0..1..1. .1..1..0..0. .1..0..0..0. .1..0..0..1 ..0..0..1..0. .0..0..1..0. .0..1..0..1. .0..1..1..1. .1..1..1..1 ..0..0..1..1. .1..1..0..1. .1..0..1..1. .1..0..0..1. .0..0..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) = a(n-1)
k=2: a(n) = 3*a(n-1) +a(n-2) -2*a(n-4)
k=3: [order 14]
k=4: [order 32] for n>35
Empirical for row n:
n=1: a(n) = a(n-1) +a(n-2)
n=2: a(n) = 2*a(n-1) +3*a(n-2) +6*a(n-3) +10*a(n-4) +4*a(n-5) for n>6
n=3: [order 15] for n>17
n=4: [order 54] for n>58
Comments