Math-y Challenge from zerocater.com/challenge

ZeroCaterPrimes.py

"""
Sunil Srivatsa - 10/22/12
Math-y Challenge from zerocater.com/challenge

Notes:
I use a .txt file of the first 78498 prime numbers from 2 to <1 million from:
http://www.svobodat.com/primes/PRIMES1T.TXT
"""
import sys, urllib2

def main():
    # keep track of the current curr_sum/chain and # of results found
    curr_sum, results = 0, 0
    chain = []
    
    # take command line input for the target # of results, default to 5
    num_results = 5
    if len(sys.argv) == 2: num_results = sys.argv[1]
        
    # fetch and sanitize list of primes
    txt = urllib2.urlopen("http://www.svobodat.com/primes/PRIMES1T.TXT")
    primes = map(int, txt.read().strip().split('\n'))

    # iterate over the primes printing the length of clean chains
    for prime in primes:
        chain.append(prime)
        curr_sum += prime
        
        if curr_sum % prime == 0:
            print len(chain)
            results += 1
 
            if results > num_results: break
    
if __name__ == '__main__':
    main()