OFFSET
1,4
COMMENTS
FORMULA
a(n) = A110218(n, n, n).
EXAMPLE
a(3) = 1, since up to rotations and reflections,
OOO KKK OOO
OKO OKO OKO
OOO OOO OOO is the only covering for n = 3.
CROSSREFS
KEYWORD
hard,more,nonn
AUTHOR
Nikolaus Meyberg (Nikolaus.Meyberg(AT)t-online.de), Jul 17 2005
STATUS
approved