

A265473


Number of n X n 0..2n2 arrays with upper left zero and lower right 2n2 and each element differing from its diagonal and antidiagonal neighbors by one or two.


0




OFFSET

1,2


COMMENTS



LINKS



EXAMPLE

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


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



