A sparse ruler is called optimal if it is both minimal and maximal. Since the number of distinct pairs of marks is m ( m â 1 ) / 2 {\displaystyle m(m-1)/2} , this is an upper bound on the length L {\displaystyle L} of any maximal sparse ruler with m {\displaystyle m} marks.
1 One 23/32-inch 4x8-foot plywood piece weighs approximately 67 pounds, while a piece of OSB of the same dimensions weighs approximately 78 pounds.
Cost. OSB costs less than plywood and is suitable for most building construction in the form of roof and side sheathing. By comparison, a typical sheet of 1/2-inch plywood sheathing at a home center or lumberyard would be nearly double the cost of a comparable thickness of OSB.SB, or oriented strand board, is a wood product made from resin and small chips of wood called strands and sold in 4-foot by 8-foot sheets, 1/4-inch and thicker.