A154037 Number of planar triangular n X n X n nonnegative integer grids symmetric under 120 degree rotation with every similarly oriented 3 X 3 X 3 subtriangle summing to 4.

0, 14, 8, 0, 29, 0, 0, 33, 0, 0, 27, 0, 0, 27, 0, 0, 27, 0, 0, 27, 0, 0, 27, 0, 0, 27, 0, 0, 27, 0, 0, 27, 0, 0, 27, 0, 0, 27, 0, 0, 27, 0, 0, 27, 0, 0, 27, 0, 0, 27, 0, 0, 27, 0, 0, 27, 0, 0

Offset

3,2

Comments

Pattern 0 0 27 starts at n=11 and continues through at least n=60.

Links

Table of n, a(n) for n=3..60.

Example

Maximal zeros solution for n=13
..............0
.............0.2
............2.0.0
...........0.0.2.0
..........0.2.0.0.2
.........2.0.0.2.0.0
........0.0.2.0.0.2.0
.......0.2.0.0.2.0.0.2
......2.0.0.2.0.0.2.0.0
.....0.0.2.0.0.2.0.0.2.0
....0.2.0.0.2.0.0.2.0.0.2
...2.0.0.2.0.0.2.0.0.2.0.0
..0.0.2.0.0.2.0.0.2.0.0.2.0

Crossrefs

Sequence in context: A033964 A275337 A337420 * A248600 A240245 A119871

Adjacent sequences: A154034 A154035 A154036 * A154038 A154039 A154040

Keyword

nonn

Author

R. H. Hardin Jan 04 2009

Status

approved