A302163 T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 1 or 3 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
1, 2, 2, 3, 3, 4, 5, 9, 6, 8, 8, 17, 7, 10, 16, 13, 25, 12, 17, 21, 32, 21, 65, 20, 29, 31, 42, 64, 34, 185, 34, 51, 73, 57, 86, 128, 55, 385, 56, 109, 140, 156, 111, 179, 256, 89, 649, 94, 206, 296, 280, 361, 265, 370, 512, 144, 1489, 156, 407, 603, 635, 621, 865, 527, 770
Offset: 1
Examples
Some solutions for n=5 k=4 ..0..1..1..0. .0..1..0..1. .0..1..0..1. .0..0..1..1. .0..1..1..0 ..0..1..0..1. .0..1..0..1. .1..0..0..1. .0..1..0..1. .0..1..0..1 ..0..1..0..1. .0..1..0..1. .1..0..1..0. .0..1..0..1. .0..1..0..1 ..0..1..0..0. .0..1..0..1. .1..0..1..0. .0..1..1..0. .1..1..0..0 ..0..1..0..1. .1..0..0..1. .1..0..1..0. .1..0..1..0. .0..1..0..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..720
Formula
Empirical for column k:
k=1: a(n) = 2*a(n-1)
k=2: a(n) = 2*a(n-1) +a(n-2) -a(n-3) -2*a(n-4) +a(n-5)
k=3: a(n) = a(n-1) +8*a(n-3) -6*a(n-4) -4*a(n-6) +4*a(n-7) for n>11
k=4: [order 15] for n>19
k=5: [order 12] for n>15
k=6: [order 15] for n>26
k=7: [order 27] for n>39
Empirical for row n:
n=1: a(n) = a(n-1) +a(n-2)
n=2: a(n) = a(n-1) +16*a(n-4) -8*a(n-5) for n>6
n=3: a(n) = a(n-1) +a(n-2) -a(n-3) +2*a(n-4) for n>6
n=4: [order 22] for n>23
n=5: [order 36] for n>40
n=6: [order 35] for n>45
n=7: [order 80] for n>89
Comments