A302472 T(n,k)=Number of nXk 0..1 arrays with every element equal to 1, 2, 3 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
0, 1, 0, 1, 3, 0, 2, 14, 11, 0, 3, 45, 49, 34, 0, 5, 146, 203, 250, 111, 0, 8, 537, 955, 1401, 1147, 361, 0, 13, 1934, 4556, 10264, 8493, 5486, 1172, 0, 21, 6861, 21843, 78679, 101109, 53575, 25599, 3809, 0, 34, 24386, 103319, 584333, 1141147, 990266, 331044
Offset: 1
Examples
Some solutions for n=5 k=4 ..0..1..0..1. .0..0..0..0. .0..1..1..1. .0..0..1..1. .0..0..1..1 ..0..0..1..1. .1..1..1..0. .0..0..1..1. .0..1..0..1. .1..0..0..0 ..1..1..1..1. .0..0..1..1. .1..1..0..1. .1..0..0..0. .1..1..1..1 ..1..0..1..0. .1..0..0..0. .1..0..0..0. .0..1..0..1. .0..0..0..1 ..0..0..0..1. .1..1..1..1. .1..1..1..0. .1..1..1..0. .1..1..1..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..180
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 43] for n>44
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 19] for n>21
n=4: [order 63] for n>66
Comments