A205155 Number of n X n 0..3 arrays with no occurrence of three equal elements in a row horizontally, vertically or nw-to-se diagonally, and new values 0..3 introduced in row major order

1, 15, 6941, 54314298, 4826926610498, 4948963310952700521

Offset

1,2

Comments

Diagonal of A205161

Links

Table of n, a(n) for n=1..6.

Example

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

Crossrefs

Sequence in context: A198250 A066968 A113795 * A208095 A271402 A205304

Adjacent sequences: A205152 A205153 A205154 * A205156 A205157 A205158

Keyword

nonn

Author

R. H. Hardin Jan 22 2012

Status

approved