A211843 Number of nonnegative integer arrays of length n+5 with new values 0 upwards introduced in order, no three adjacent elements all unequal, and containing the value 3.

1, 7, 35, 147, 561, 2013, 6936, 23244, 76434, 248158, 799178, 2561866, 8197109, 26236283, 84147409, 270824081, 875656255, 2846900003, 9313478684, 30675454100, 101762486216, 340118043072, 1145518666868, 3888262008004, 13301838021901

Offset: 1

Author

R. H. Hardin Apr 22 2012

Keywords

• nonn

Comments

Column 2 of A211849

Examples

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

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210