A233260 Number of 5Xn 0..5 arrays with no element x(i,j) adjacent to itself or value 5-x(i,j) horizontally or antidiagonally, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order (unlabeled 6-colorings with no clashing color pairs).

236, 32896, 10620928, 3439984640, 1159192379392, 393427728465920, 134179300927602688, 45829217084770353152, 15662712220567239393280, 5353914504847465071509504, 1830206096861520940880625664

Offset: 1

Author

R. H. Hardin, Dec 06 2013

Keywords

• nonn

Comments

Row 5 of A233256

Examples

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

Links

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

Formula

Empirical: a(n) = 512*a(n-1) -65536*a(n-2) +2490368*a(n-3) [phone]*a(n-4) -2818572288*a(n-5) [phone]*a(n-6) -274877906944*a(n-7) for n>11