A242471 Number of length n+2 0..8 arrays with no three equal elements in a row and new values 0..8 introduced in 0..8 order.

4, 12, 41, 159, 685, 3233, 16534, 90862, 532958, 3317613, 21803646, 150528288, 1086089333, 8146481406, 63182485967, 504037166445, 4115582321241, 34244236336515, 289252828167957, 2472398717507023, 21329556857593204

Offset: 1

Author

R. H. Hardin, May 15 2014

Keywords

• nonn

Comments

Column 8 of A242472

Examples

			Some solutions for n=5
..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....0....1....1....1....1....1....0
..2....2....2....1....2....1....2....1....2....1....2....1....1....2....2....1
..3....3....2....2....2....0....3....2....3....2....3....2....0....3....3....2
..0....0....3....2....1....2....0....2....4....3....2....2....1....0....4....0
..4....4....4....0....2....2....2....3....2....4....0....1....1....3....1....3
..0....5....4....1....1....3....4....3....1....3....4....3....2....1....2....1
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..133

Formula

Empirical: a(n) = 29*a(n-1) -314*a(n-2) +1449*a(n-3) -1442*a(n-4) -8855*a(n-5) +16059*a(n-6) +34312*a(n-7) -42104*a(n-8) -101900*a(n-9) -6124*a(n-10) +112608*a(n-11) +106128*a(n-12) +40320*a(n-13) +5760*a(n-14)