A271333 Number of nXnXn triangular 0..1 arrays with new values introduced in sequential zero-upwards order and exactly one upright 2x2x2 triangle having values all equal.

0, 1, 15, 207, 3283, 64650, 1640007, 54704700, 2429994600, 144950275305, 11678538065077, 1276251983814717, 189767651505152535, 38484504169958401936, 10664509514660169498882, 4044220867954839169651680

Offset

1,3

Comments

Column 1 of A271339.

Links

R. H. Hardin, Table of n, a(n) for n = 1..20

Example

Some solutions for n=4
.....0........0........0........0........0........0........0........0
....1.1......0.1......0.1......1.0......0.1......1.1......1.0......0.1
...0.1.0....1.1.1....1.0.0....1.1.0....1.1.0....1.0.1....1.0.0....0.0.0
..0.0.0.1..0.1.0.1..1.1.1.1..0.0.1.0..1.0.0.0..0.0.0.0..0.0.1.1..0.1.1.1

Crossrefs

Cf. A271339.

Sequence in context: A194481 A078265 A089138 * A051813 A280160 A239991

Adjacent sequences: A271330 A271331 A271332 * A271334 A271335 A271336

Keyword

nonn

Author

R. H. Hardin, Apr 04 2016

Status

approved