A207305 T(n,k)=Number of nXk 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 0 1 and 1 1 0 vertically.
2, 4, 4, 6, 16, 6, 9, 36, 36, 8, 13, 81, 98, 64, 10, 19, 169, 271, 200, 100, 12, 28, 361, 665, 643, 350, 144, 14, 41, 784, 1675, 1759, 1271, 556, 196, 16, 60, 1681, 4344, 4939, 3773, 2239, 826, 256, 18, 88, 3600, 11081, 14446, 11497, 7093, 3641, 1168, 324, 20, 129
Offset: 1
Examples
Some solutions for n=4 k=3 ..1..1..1....0..1..0....1..1..0....0..0..1....1..1..0....0..1..0....1..0..0 ..1..1..1....1..1..0....0..0..1....0..0..1....1..0..0....0..1..0....0..0..1 ..1..1..1....0..1..0....1..1..1....0..0..1....1..0..0....0..1..0....1..0..0 ..1..1..1....1..1..0....1..1..1....0..0..1....1..0..0....0..1..0....0..0..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..480
Crossrefs
Formula
Empirical for column k:
k=1: a(n) = 2*n
k=2: a(n) = 4*n^2
k=3: a(n) = (4/3)*n^3 + 8*n^2 - (10/3)*n
k=4: a(n) = (5/12)*n^4 + (13/2)*n^3 + (115/12)*n^2 - (17/2)*n + 1
k=5: a(n) = (8/3)*n^4 + (49/3)*n^3 + (16/3)*n^2 - (43/3)*n + 3
k=6: a(n) = (4/15)*n^5 + (45/4)*n^4 + (199/6)*n^3 - (73/4)*n^2 - (373/30)*n + 5
k=7: a(n) = (187/60)*n^5 + (153/4)*n^4 + (455/12)*n^3 - (249/4)*n^2 + (209/30)*n + 4
Comments