A154052 Number of planar triangular n X n X n nonnegative integer grids symmetric both under 120 degree rotation and reflection with every similarly oriented 5 X 5 X 5 subtriangle summing to 5.

0, 5, 8, 0, 2, 3, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0

Offset

5,2

Comments

Pattern 1 0 0 starts at n=13 and continues through at least n=60.

Links

Table of n, a(n) for n=5..60.

Example

Maximal zeros solution for n=13
..............1
.............0.0
............0.1.0
...........1.0.0.1
..........0.0.1.0.0
.........0.1.0.0.1.0
........1.0.0.1.0.0.1
.......0.0.1.0.0.1.0.0
......0.1.0.0.1.0.0.1.0
.....1.0.0.1.0.0.1.0.0.1
....0.0.1.0.0.1.0.0.1.0.0
...0.1.0.0.1.0.0.1.0.0.1.0
..1.0.0.1.0.0.1.0.0.1.0.0.1

Crossrefs

Sequence in context: A249403 A201756 A242674 * A181439 A011496 A198360

Adjacent sequences: A154049 A154050 A154051 * A154053 A154054 A154055

Keyword

nonn

Author

R. H. Hardin Jan 04 2009

Status

approved