A154095 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 15.

34, 71, 166, 99, 63, 160, 77, 49, 77, 38, 24, 64, 20, 26, 24, 20, 21, 32, 18, 20

Offset

5,1

Links

Table of n, a(n) for n=5..24.

Example

Maximal zeros solution for n=20
.....................3
....................3.3
...................0.1.0
..................0.0.0.0
.................0.1.3.1.0
................0.0.3.3.0.0
...............3.1.0.1.0.1.3
..............3.3.0.0.0.0.3.3
.............0.1.0.1.3.1.0.1.0
............0.0.0.0.3.3.0.0.0.0
...........0.1.3.1.0.1.0.1.3.1.0
..........0.0.3.3.0.0.0.0.3.3.0.0
.........3.1.0.1.0.1.3.1.0.1.0.1.3
........3.3.0.0.0.0.3.3.0.0.0.0.3.3
.......0.1.0.1.3.1.0.1.0.1.3.1.0.1.0
......0.0.0.0.3.3.0.0.0.0.3.3.0.0.0.0
.....0.1.3.1.0.1.0.1.3.1.0.1.0.1.3.1.0
....0.0.3.3.0.0.0.0.3.3.0.0.0.0.3.3.0.0
...3.1.0.1.0.1.3.1.0.1.0.1.3.1.0.1.0.1.3
..3.3.0.0.0.0.3.3.0.0.0.0.3.3.0.0.0.0.3.3

Crossrefs

Sequence in context: A044517 A063333 A079863 * A184066 A277449 A063533

Adjacent sequences: A154092 A154093 A154094 * A154096 A154097 A154098

Keyword

nonn

Author

R. H. Hardin Jan 04 2009

Status

approved