A217228 Number of triangular nXnXn arrays of occupancy after each element moves to some neighbor but without 2-loops and with no occupancy greater than 2.

0, 1, 26, 1755, 321848, 178829423

Offset

1,3

Comments

Column 2 of A217232

Links

Table of n, a(n) for n=1..6.

Example

Some solutions for n=4
.....1........1........1........0........0........0........0........0
....2.1......2.2......2.2......1.2......1.1......1.1......1.2......2.0
...2.0.1....1.1.2....2.1.0....1.1.2....1.2.1....1.1.2....1.1.1....1.1.2
..0.1.1.1..0.1.0.0..1.0.1.0..1.2.0.0..1.0.2.1..1.1.1.1..1.2.1.0..0.1.2.1

Crossrefs

Sequence in context: A080163 A368852 A300578 * A005644 A123537 A220503

Adjacent sequences: A217225 A217226 A217227 * A217229 A217230 A217231

Keyword

nonn,hard,more

Author

R. H. Hardin Sep 28 2012

Status

approved