A243606 Number of length n+2 0..9 arrays with no three elements in a row with pattern aba (with a!=b) and new values 0..9 introduced in 0..9 order.

4, 10, 29, 97, 366, 1534, 7050, 35167, 188834, 1084123, 6616633, 42711918, 290232665, 2066233824, 15337289086, 118111928594, 938944428249, 7667833845713, 64035036092080, 544629289107076, 4700922875545352

Offset: 1

Author

R. H. Hardin, Jun 07 2014

Keywords

• nonn

Comments

Column 9 of A243607

Examples

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

Links

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

Formula

Empirical: a(n) = 38*a(n-1) -603*a(n-2) +5165*a(n-3) -25592*a(n-4) +71533*a(n-5) -92714*a(n-6) -10048*a(n-7) +134330*a(n-8) -29886*a(n-9) -94396*a(n-10) -8366*a(n-11) +29547*a(n-12) +16394*a(n-13) +4033*a(n-14) +529*a(n-15) +36*a(n-16) +a(n-17)