A271028 Number of nXnXn triangular 0..2 arrays with some element less than a w, nw or ne neighbor exactly once.

0, 8, 72, 450, 2420, 12010, 56754, 259628, 1160936, 5105144, 22166760, 95301932, 406510934, 1722863088, 7263024536, 30481913682, 127442700854, 531088604958, 2206913662766, 9147940180122, 37836235984334, 156187232759706

Offset

1,2

Comments

Column 2 of A271034.

Links

R. H. Hardin, Table of n, a(n) for n = 1..30

Example

Some solutions for n=4
.....0........1........0........0........1........2........0........0
....0.0......1.1......0.1......0.0......1.1......2.2......1.2......0.2
...0.0.0....1.1.2....1.1.1....2.0.1....0.1.1....0.2.2....2.2.2....0.2.2
..0.2.2.1..0.2.2.2..0.1.1.1..2.2.2.2..0.1.1.1..0.2.2.2..0.2.2.2..0.1.2.2

Crossrefs

Cf. A271034.

Sequence in context: A143945 A239095 A189954 * A180288 A082141 A304826

Adjacent sequences: A271025 A271026 A271027 * A271029 A271030 A271031

Keyword

nonn

Author

R. H. Hardin, Mar 29 2016

Status

approved