A208045 Number of n X n 0..3 arrays with new values 0..3 introduced in row major order and no element equal to any horizontal, vertical or antidiagonal neighbor (colorings ignoring permutations of colors)

1, 2, 44, 1904, 168096, 30818432, 11838995200, 9578237457408, 16372889877477376, 59262411624914853888, 454901302416508366209024, 7413673375795915677473636352

Offset

1,2

Comments

Diagonal of A208050

Links

Table of n, a(n) for n=1..12.

Example

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

Mathematica

A208050 = Cases[Import["https://oeis.org/A208050/b208050.txt", "Table"], {_, _}][[All, 2]];
a[n_] := A208050[[2 n^2 - 2 n + 1]];
Table[a[n], {n, 1, 12}] (* Jean-François Alcover, Sep 23 2019 *)

Crossrefs

Sequence in context: A213067 A140795 A161744 * A267070 A054732 A161722

Adjacent sequences: A208042 A208043 A208044 * A208046 A208047 A208048

Keyword

nonn

Author

R. H. Hardin Feb 22 2012

Status

approved