# Problem 161: Triominoes
A triomino is a shape consisting of three squares joined via the edges.
There are two basic forms: If all possible orientations are taken into
account there are six: Any n by m grid for which nxm is divisible by 3
can be tiled with triominoes. If we consider tilings that can be
obtained by reflection or rotation from another tiling as different
there are 41 ways a 2 by 9 grid can be tiled with triominoes: In how
many ways can a 9 by 12 grid be tiled in this way by triominoes?