Are you re-building or just add another layer? It seems cheap. And which state are you in?
【在 N**s 的大作中提到】 : we spent $4250 totally paving asphalt driveway appx. 195ft x 10ft.
C*a
14 楼
1. it is a prime only if it does not have any prime factor that is less than the root of itself. 2. Assume we had found out the first (n-1) primes, store them in an array ( or a list), and then check the numbers(>(n-1)th prime) to see if it is a prime ( use 1. to judge).