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.
OSB, 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.The common thickness for sheathing a home is 1/2 inch.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.