A232378 Number of 3Xn 0..3 arrays with every 0 next to a 1, every 1 next to a 2 and every 2 next to a 3 horizontally, diagonally or antidiagonally, and no adjacent values equal.

1, 58, 586, 4404, 32722, 259458, 2046700, 16005328, 125458506, 984034642, 7715900888, 60499523096, 474378832026, 3719632557790, 29165838646828, 228690711059796, 1793174932294258, 14060373065557530, 110248073913792604

Offset: 1

Author

R. H. Hardin, Nov 23 2013

Keywords

• nonn

Comments

Row 3 of A232376

Examples

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

Links

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

Formula

Empirical: a(n) = 6*a(n-1) +4*a(n-2) +69*a(n-3) +48*a(n-4) +355*a(n-5) +241*a(n-6) +1332*a(n-7) +2318*a(n-8) +448*a(n-9) -1416*a(n-10) -784*a(n-11) +64*a(n-12) +48*a(n-13) for n>14