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.
There's no price savings at all using Struct 1 OSB versus Struct 1 CDX plywood , but there's a big difference in the price for CDX 5 ply plywood versus OSB Struct 2. SBE Builders will only use CDX plywood or OSB that has a APA rated sheathing stamp with a EXPOSURE 1 stamp. This APA stamp guarantees that waterproof resins and glues were used to bond the CDX plywood or OSB to the wood fibers. EXPOSURE 1 CDX plywood and OSB are made to withstand repeated rainfall with little or no damage during a normal time frame construction project. However, the creep - edge swelling of OSB does pose problems when OSB is used for subfloors that receive ceramic title as a finished floor.