A208052 Number of n X 4 nonnegative integer arrays with new values 0 upwards introduced in row major order and no element equal to any horizontal, vertical or antidiagonal neighbor (colorings ignoring permutations of colors).

5, 203, 83440, 112073062, 346212384169, 2043836452962923, 20538493062072286871, 324446721789278481458200, 7600607444778834885508561198, 252518539060608935260165703671351, 11485037650037932819944784728914383376, 694873103685620467779932914106484450991930

Offset: 1

Author

R. H. Hardin, Feb 22 2012

Keywords

• nonn

Examples

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

Links

• Andrew Howroyd, Table of n, a(n) for n = 1..50

Crossrefs

Column 4 of A208054.

Extensions

Terms a(11) and beyond from Andrew Howroyd, Jun 25 2017