Figure P shows a square tile with a 4×4 grid marked on it. One of the ways the tile can be cut along the grid lines into two similar and contiguous pieces is shown in figure Q. The different configurations of this cut, shown in figure R, are counted as the same cut. In how many ways, excluding the cut shown in Q, can the tile be cut into two similar and contiguous pieces along the grid lines? [Figure: see page 19 of source PDF]