A203649 1/25 the number of (n+1)X(n+1) 0..4 arrays with every 2X2 subblock having equal diagonal elements or equal antidiagonal elements

9, 1517, 1116249, 3906948333, 67213191427593, 5796397762880763341

Offset

1,1

Comments

Diagonal of A203656

Links

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

Example

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

Crossrefs

Sequence in context: A231191 A217267 A300594 * A187131 A167774 A197206

Adjacent sequences: A203646 A203647 A203648 * A203650 A203651 A203652

Keyword

nonn

Author

R. H. Hardin Jan 04 2012

Status

approved