A198701 Number of n X n 0..4 arrays with values 0..4 introduced in row major order and each element equal to at least one horizontal or vertical neighbor.

0, 3, 185, 322230, 10239497407, 4285681886701131

Offset

1,2

Links

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

Example

Some solutions with all values 0 to 4 for n=4:
..0..0..1..2....0..1..2..2....0..1..2..2....0..1..2..1....0..0..0..1
..3..3..1..2....0..1..1..3....0..1..3..3....0..1..2..1....2..0..1..1
..3..0..4..4....0..4..4..3....2..2..2..4....1..3..4..4....2..3..3..1
..0..0..0..4....2..2..1..1....1..1..2..4....1..3..3..3....4..4..1..1

Crossrefs

Diagonal of A198708.

Sequence in context: A103503 A203562 A371153 * A157561 A157590 A157236

Adjacent sequences: A198698 A198699 A198700 * A198702 A198703 A198704

Keyword

nonn,more

Author

R. H. Hardin, Oct 29 2011

Status

approved