A266067 T(n,k)=Number of nXk integer arrays with each element equal to the number of horizontal, vertical, diagonal and antidiagonal neighbors exactly one smaller than itself.
1, 3, 3, 4, 17, 4, 5, 35, 35, 5, 9, 89, 34, 89, 9, 16, 323, 81, 81, 323, 16, 25, 1057, 809, 525, 809, 1057, 25, 39, 3027, 1750, 8262, 8262, 1750, 3027, 39, 64, 9257, 5071, 25663, 154939, 25663, 5071, 9257, 64, 105, 29835, 29256, 148323, 1066148, 1066148, 148323
Offset: 1
Examples
Some solutions for n=4 k=4 ..0..0..0..1....2..1..0..0....1..0..0..1....1..0..0..0....1..1..2..0 ..0..2..3..2....1..3..2..0....2..2..2..2....1..2..3..0....0..2..2..1 ..1..1..2..1....2..0..3..1....1..3..3..1....2..2..2..0....0..3..2..2 ..2..3..2..0....1..2..1..2....0..1..1..0....0..1..2..1....0..0..0..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..84
Crossrefs
Column 1 is A195971.
Formula
Empirical for column k:
k=1: a(n) = a(n-1) +a(n-3) +a(n-4)
k=2: [order 18]
k=3: [order 78]
Comments