Версия генератора простых чисел на Python:

def genPrimes():
    prime  = 2
    primes = [ prime ]
    yield prime
    while True:
        prime += 1
        is_prime = 0
        for i in primes:
            if prime % i != 0:
                is_prime += 1
        if is_prime == len(primes):
            primes.append(prime)
            yield prime