Porting optimized Sieve of Eratosthenes from Python to C++

Question

Some time ago I used the (blazing fast) primesieve in python that I found here: Fastest way to list all primes below N

To be precise, this implementation:

Answer 1

Piggy-Backing onto Howard Hinnant's response, Howard, you don't have to test numbers in the set of all natural numbers not divisible by 2, 3 or 5 for primality, per se. You need simply multiply each number in the array (except 1, which self-eliminates) times itself and every subsequent number in the array. These overlapping products will give you all the non-primes in the array up to whatever point you extend the deterministic-multiplicative process. Thus the first non-prime in the array will be 7 squared, or 49. The 2nd, 7 times 11, or 77, etc. A full explanation here: http://www.primesdemystified.com