OFFSET
1,3
COMMENTS
Row 7 of A187857
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..50
FORMULA
Empirical: a(n) = 211612*n^2 - 1941340*n + 4328678 for n>11
EXAMPLE
Some solutions for 4X4
..0..3..5..4....0..0..4..0....0..0..0..0....0..3..2..0....0..1..0..0
..1..7..2..0....7..6..0..3....0..4..0..7....1..0..0..6....4..0..7..0
..0..0..6..0....0..5..0..2....0..3..2..6....0..4..0..5....3..2..6..0
..0..0..0..0....0..1..0..0....0..5..0..1....0..0..7..0....0..0..5..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin Mar 14 2011
STATUS
approved