A208306 Number of 6 X n nonnegative integer arrays with new values 0 upwards introduced in row major order and no element equal to any horizontal or antidiagonal neighbor (colorings ignoring permutations of colors).

1, 203, 678570, 46538017584, 17131843186425504, 21183598567292002167082, 67939294184937980415465539016, 479196921365748673300774676923278618, 6626004995909411145707148239379062019989108, 164986885310084515129040822858386474548745376110410

Offset

0,2

Links

Andrew Howroyd, Table of n, a(n) for n = 0..50

Example

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

Crossrefs

Row 6 of A208301.

Sequence in context: A209525 A145635 A319783 * A208786 A208586 A208465

Adjacent sequences: A208303 A208304 A208305 * A208307 A208308 A208309

Keyword

nonn

Author

R. H. Hardin, Feb 25 2012

Extensions

a(0)=1 prepended and terms a(6) and beyond from Andrew Howroyd, May 18 2020

Status

approved