A194574 Number of lower triangles of an n X n 0..6 array with new values introduced in row major order 0..6 and no element equal to more than two horizontal or vertical neighbors

1, 5, 194, 109314, 1023490379, 103716766788027, 80480437921181928079, 438719474917484694724554104

Offset

1,2

Comments

Column 6 of A194576

Links

Table of n, a(n) for n=1..8.

Example

Some solutions for 3X3
..0......0......0......0......0......0......0......0......0......0......0
..0.0....1.0....1.0....1.0....1.2....0.0....1.2....0.1....1.1....1.2....0.1
..1.0.2..0.0.1..2.1.1..2.3.3..0.1.0..1.2.3..3.2.3..0.1.0..2.3.1..3.0.0..2.1.3

Crossrefs

Sequence in context: A194572 A068793 A194573 * A194575 A240772 A142927

Adjacent sequences: A194571 A194572 A194573 * A194575 A194576 A194577

Keyword

nonn

Author

R. H. Hardin Aug 29 2011

Status

approved