A183278 Half the number of n X n X n triangular binary arrays with no array-aligned 2 X 2 X 2 subtriangle being all zero or all one.

1, 3, 13, 80, 693, 8407, 142362, 3357612, 110120153, 5016480073, 317135545779, 27803984036400, 3378700619148221, 568830517952061132, 132632829107728951932, 42817890108690930718624

Offset

1,2

Links

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

Example

Some solutions for 6X6X6 with a(1,1)=0
.......0............0............0............0............0............0
......0.1..........0.1..........1.1..........1.1..........1.1..........1.0
.....1.1.0........1.1.0........1.0.0........0.1.0........0.0.0........0.0.1
....0.0.1.0......0.1.0.1......0.1.0.1......1.0.1.1......0.1.1.0......0.1.0.0
...0.1.1.0.1....1.0.0.1.0....1.0.0.1.0....0.1.0.1.0....0.1.0.1.0....1.0.0.1.1
..1.0.0.1.1.0..0.0.1.0.1.0..0.0.1.0.1.0..1.0.1.0.1.1..1.1.0.1.0.1..1.0.1.0.1.0

Crossrefs

Sequence in context: A366179 A201795 A308521 * A331643 A074514 A020014

Adjacent sequences: A183275 A183276 A183277 * A183279 A183280 A183281

Keyword

nonn

Author

R. H. Hardin, Jan 03 2011

Status

approved