OFFSET
1,1
COMMENTS
Column 5 of A253011
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 2973696*n^3 - 70716096*n^2 + 570494664*n - 1560617160 for n>12
EXAMPLE
Some solutions for n=6
..0..0..0..0..0....0..0..0..0..0....0..0..0..0..1....0..1..1..1..1
..1..1..1..1..1....0..0..1..1..1....0..0..0..1..1....0..1..1..1..2
..1..1..1..1..1....0..0..1..1..1....0..0..1..1..1....1..1..1..1..2
..1..1..1..1..2....0..0..1..1..1....0..0..1..1..1....1..1..1..1..2
..1..2..2..2..2....0..0..1..2..2....0..1..1..1..2....1..1..1..1..2
..1..2..2..2..2....0..0..1..2..2....1..1..1..1..2....1..1..1..1..2
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 25 2014
STATUS
approved