Euler #58

def prime(n):
    if n == 2 or n == 3: return True
    if n < 2 or n % 2 == 0: return False
    if n < 9: return True
    if n % 3 == 0: return False
    r = int(n**0.5)
    f = 5
    while f <= r:
        if n % f == 0: return False
        if n % (f+2) == 0: return False
        f += 6
    return True

square, inc, runningtotal, total, primes = 3, 4, 9, 5, 3
while (primes/total) > 0.1:
    for x in range(4):
        runningtotal += inc
        total += 1
        if prime(runningtotal):
            primes += 1
    square += 2
    inc += 2
    print(square)
print(square)