A270504 Number of nXnXn triangular 0..2 arrays with some element plus some adjacent element totalling 2+1 exactly once.

0, 6, 144, 5406, 369072, 47829828, 12072484260, 6018099563412, 5978376752357856, 11906720428681033194, 47747190052669169665500, 386741181278527199554452264, 6342331030790597545544573997684

Offset

1,2

Comments

Column 2 of A270509.

Links

R. H. Hardin, Table of n, a(n) for n = 1..16

Example

Some solutions for n=4
.....2........1........0........2........0........1........1........1
....0.1......0.0......0.1......0.0......0.1......1.0......2.0......1.1
...0.1.1....0.0.2....0.0.0....1.1.1....2.2.0....1.1.0....0.0.0....1.1.0
..0.1.1.0..1.1.1.0..1.2.2.0..1.0.0.2..0.2.0.2..2.0.0.1..0.1.1.1..0.0.2.0

Crossrefs

Cf. A270509.

Sequence in context: A197178 A208230 A010043 * A085905 A203978 A090443

Adjacent sequences: A270501 A270502 A270503 * A270505 A270506 A270507

Keyword

nonn

Author

R. H. Hardin, Mar 18 2016

Status

approved