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

1,1

Links

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

Example

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

Crossrefs

Column 4 of A208054.

Sequence in context: A215923 A208468 A070906 * A137736 A157389 A128678

Adjacent sequences: A208049 A208050 A208051 * A208053 A208054 A208055

Keyword

nonn

Author

R. H. Hardin, Feb 22 2012

Extensions

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

Status

approved