When I get 2x4' at Lowes' and they ask me how many they are, I tell them I am a carpenter not a mathematician. You guys give me a headache.
Counting has been previously invented. Not sure it can be patented tho! Too many people use this these days, and the origins probably pre date engineers and lawyers, so we are pretty much screwed for making any claim as to absolute rights of knowing how many 2x4's you purchased at Lowes.
Make sure the gal at checkout with the bar code scanner didn't trip something twice, and always check your receipts before leaving the store.
