A203113 Number of n X n X n 0..6 triangular arrays with each element x equal to the number its neighbors equal to 3,1,2,1,2,0,2 for x=0,1,2,3,4,5,6.

1, 5, 20, 208, 3516, 108850, 6900201, 776174640, 167355580505, 68493666999406

Offset

1,2

Comments

Every 0 is next to 0 3's, every 1 is next to 1 1's, every 2 is next to 2 2's, every 3 is next to 3 1's, every 4 is next to 4 2's, every 5 is next to 5 0's, every 6 is next to 6 2's.

Links

Table of n, a(n) for n=1..10.

Example

Some solutions with all values from 0 to 6 for 7 X 7 X 7
........0..............0..............1..............0..............0
.......0.2............0.0............2.1............1.0............0.0
......0.2.2..........0.5.0..........2.2.3..........1.2.2..........0.5.0
.....0.0.4.1........1.0.2.2........0.4.1.1........0.2.6.2........1.0.2.2
....0.0.2.2.1......3.1.2.6.2......0.2.2.0.0......2.4.2.2.0......3.1.2.6.2
...0.5.2.6.2.3....1.2.4.2.2.1....0.2.6.2.5.0....2.2.1.0.5.0....1.2.4.2.2.0
..0.0.0.2.2.1.1..1.2.2.0.0.0.1..1.1.2.2.0.0.0..1.1.3.1.0.0.0..1.2.2.1.1.0.0

Crossrefs

Sequence in context: A189317 A203902 A000877 * A077817 A032324 A321214

Adjacent sequences: A203110 A203111 A203112 * A203114 A203115 A203116

Keyword

nonn

Author

R. H. Hardin, Dec 29 2011

Status

approved