A222920 Number of nX2 0..4 arrays with no three equal values in a row horizontally or vertically, and new values 0..4 introduced in row major order.

2, 15, 174, 3183, 68076, 1543538, 35663142, 829049736, 19310392822, 450063924406, 10491666753024, 244592254688694, 5702297247404918, 132941283209423448, 3099351244544272614, 72257348464516101894, 1684586587434789765504

Offset: 1

Author

R. H. Hardin Mar 09 2013

Keywords

• nonn

Comments

Column 2 of A222924

Examples

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

Links

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

Formula

Empirical: a(n) = 28*a(n-1) -78*a(n-2) -789*a(n-3) +1250*a(n-4) +3796*a(n-5) -3288*a(n-6) -2208*a(n-7) +2432*a(n-8) -512*a(n-9) for n>11