A216790 Number of 4-colorings of a side-n hexagonal array with colors introduced in row major order.

1, 11, 5318, 22831676, 915294166360, 348567447145791344

Offset: 1

Author

R. H. Hardin Sep 16 2012

Keywords

• nonn

Comments

Column 3 of A216792

Examples

			Some solutions for n=3
......0.1.2..........0.1.2..........0.1.2..........0.1.2..........0.1.2
.....1.3.0.1........1.2.0.3........3.2.3.0........3.2.0.1........3.2.3.0
....3.2.1.2.0......0.3.1.2.1......2.0.1.2.1......2.0.3.2.3......2.1.0.2.1
.....0.3.0.3........1.0.3.0........3.2.0.3........1.2.0.1........0.2.1.3
......2.1.2..........3.1.2..........0.3.2..........0.1.3..........1.3.0