A197889 T(n,k)=Number of nXk 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 0,2,1,1,1 for x=0,1,2,3,4.
1, 0, 0, 1, 4, 1, 2, 3, 3, 2, 1, 14, 6, 14, 1, 1, 18, 47, 47, 18, 1, 3, 43, 77, 155, 77, 43, 3, 3, 78, 196, 835, 835, 196, 78, 3, 2, 154, 529, 2263, 2730, 2263, 529, 154, 2, 4, 305, 1637, 10827, 17890, 17890, 10827, 1637, 305, 4, 6, 572, 4235, 38938, 92843, 129294, 92843
Offset: 1
Examples
Some solutions containing all values 0 to 4 for n=6 k=4 ..1..2..2..1....0..2..1..0....0..1..2..0....1..2..0..1....1..2..2..1 ..3..1..1..0....1..1..1..2....2..1..1..1....3..1..1..2....0..1..1..0 ..1..4..1..2....2..1..4..1....1..4..1..2....1..4..1..2....1..4..1..2 ..2..1..4..1....2..1..1..3....0..1..1..2....2..1..4..1....2..1..3..1 ..0..1..1..3....1..0..2..1....1..2..3..1....2..1..1..3....2..1..3..1 ..1..2..2..1....0..1..2..1....1..2..1..0....1..0..2..1....1..0..1..2
Links
- R. H. Hardin, Table of n, a(n) for n = 1..144
Crossrefs
Column 1 is A017817(n+3)
Comments