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.
Its superior performance has allowed OSB to gain popularity in a variety of other areas, including: structural insu-. lated panels, the webs for wood I-joists, materials-handling applications, furniture, and a variety of do-it-yourself projects. OSB panels manufactured in North America are typically 4 x 8 feet in size.