A215071 Number of squarefree words of length n in a 5-ary alphabet, with new values 0..4 introduced in increasing order.

1, 1, 2, 4, 12, 39, 138, 503, 1864, 6936, 25868, 96512, 360203, 1344408, 5018051, 18729944, 69910398, 260943079, 973980990, 3635421345, 13569354266, 50648137765, 189046143161

Offset: 1

Author

R. H. Hardin Aug 02 2012

Keywords

• nonn

Comments

Column 4 of A215075

Examples

			Some solutions for n=6
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..1....1....1....1....1....1....1....1....1....1....1....1....1....1....1....1
..2....2....2....2....0....2....2....2....0....2....2....0....2....2....0....2
..0....3....3....1....2....3....3....1....2....1....0....2....0....3....2....3
..1....4....0....3....3....0....0....3....3....3....3....3....2....2....0....1
..0....0....1....2....0....2....3....4....1....0....4....4....1....4....3....0