A154041 Number of planar triangular n X n X n nonnegative integer grids with mirror symmetry about one altitude with every similarly oriented 4 X 4 X 4 subtriangle summing to 4.

27, 96, 52, 70, 23, 27, 16, 15, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8

Offset

4,1

Comments

Value 8 starts at n=12 and continues through at least n=60.

Links

Table of n, a(n) for n=4..60.

Example

Maximal zeros solution for n=12
.............2
............0.0
...........0.2.0
..........0.0.0.0
.........0.0.2.0.0
........2.0.0.0.0.2
.......0.0.0.2.0.0.0
......0.2.0.0.0.0.2.0
.....0.0.0.0.2.0.0.0.0
....0.0.2.0.0.0.0.2.0.0
...2.0.0.0.0.2.0.0.0.0.2
..0.0.0.2.0.0.0.0.2.0.0.0

Crossrefs

Sequence in context: A226359 A078183 A072252 * A233156 A118615 A197619

Adjacent sequences: A154038 A154039 A154040 * A154042 A154043 A154044

Keyword

nonn

Author

R. H. Hardin Jan 04 2009

Status

approved