A154050 Number of planar triangular n X n X n nonnegative integer grids symmetric under 120 degree rotation with every similarly oriented 5 X 5 X 5 subtriangle summing to 5.

0, 25, 72, 0, 28, 61, 0, 13, 43, 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

5,2

Comments

Pattern 0 0 27 starts at n=14 and continues through at least n=57.

Links

Table of n, a(n) for n=5..57.

Example

Maximal zeros solution for n=16
.................0
................0.1
...............1.0.0
..............0.0.1.0
.............0.0.0.1.1
............1.0.0.1.0.0
...........0.1.1.0.0.0.0
..........0.1.0.0.1.0.0.1
.........1.0.0.0.0.1.1.0.0
........0.0.1.0.0.1.0.0.1.0
.......0.0.0.1.1.0.0.0.0.1.1
......1.0.0.1.0.0.1.0.0.1.0.0
.....0.1.1.0.0.0.0.1.1.0.0.0.0
....0.1.0.0.1.0.0.1.0.0.1.0.0.1
...1.0.0.0.0.1.1.0.0.0.0.1.1.0.0
..0.0.1.0.0.1.0.0.1.0.0.1.0.0.1.0

Crossrefs

Sequence in context: A087239 A032653 A063308 * A182323 A255184 A235941

Adjacent sequences: A154047 A154048 A154049 * A154051 A154052 A154053

Keyword

nonn

Author

R. H. Hardin Jan 04 2009

Status

approved