A230750 Number of (n+3)X(1+3) 0..2 arrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 3, and upper left element zero.

12, 192, 2700, 31212, 363312, 4120752, 46949808, 532746828, 6052341168, 68709570732, 780232681452, 8858778163392, 100588142063808, 1142112286468800, 12968074244891052, 147244827712021248, 1671881661357048300

Offset: 1

Author

R. H. Hardin, Oct 29 2013

Keywords

• nonn

Comments

Column 1 of A230757

Examples

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

Links

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

Formula

Empirical: a(n) = 12*a(n-1) +18*a(n-2) -330*a(n-3) +381*a(n-4) +1326*a(n-5) -1995*a(n-6) -1701*a(n-7) +2955*a(n-8) +462*a(n-9) -1434*a(n-10) +147*a(n-11) +198*a(n-12) -33*a(n-13) -6*a(n-14) +a(n-15)