A154035 Number of planar triangular n X n X n nonnegative integer grids with mirror symmetry about one altitude with every similarly oriented 5 X 5 X 5 subtriangle summing to 3.

28, 42, 30, 16, 5, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1

Offset

5,1

Comments

Value 1 starts at n=11 and continues through at least n=60.

Links

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

Example

Maximal zeros solution for n=11
............1
...........0.0
..........0.1.0
.........0.0.0.0
........0.0.1.0.0
.......1.0.0.0.0.1
......0.0.0.1.0.0.0
.....0.1.0.0.0.0.1.0
....0.0.0.0.1.0.0.0.0
...0.0.1.0.0.0.0.1.0.0
..1.0.0.0.0.1.0.0.0.0.1

Crossrefs

Sequence in context: A047630 A135789 A219882 * A025368 A025359 A056031

Adjacent sequences: A154032 A154033 A154034 * A154036 A154037 A154038

Keyword

nonn

Author

R. H. Hardin Jan 04 2009

Status

approved