Created
October 21, 2010 23:03
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Rodrigo Farnham's readable Python solution to GPCv1 Level 2
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def getPrimes(n = 1000000): | |
#Generate list of primes using the sieve of Eratosthenes | |
#the list was arbitrarily chosen to include positive integers | |
#up to 10**6 and it turned out to be enough | |
primes = range(n) | |
primes[1] = 0 | |
for p in primes: | |
if p: | |
x = 2*p | |
while x < n: | |
primes[x] = 0 | |
x += p | |
return [p for p in primes if p] | |
def Fib(): | |
#Generator for Fibonacci numbers | |
a = 1 | |
b = 1 | |
while True: | |
yield a | |
c = a + b | |
a = b | |
b = c | |
def primeDivs(n, primes = getPrimes()): | |
lst = [] | |
for p in primes: | |
if n % p == 0: | |
lst.append(p) | |
while n % p == 0: | |
n /= p | |
return lst | |
primes = getPrimes() | |
for x in Fib(): | |
if x > 227000 and x in primes: | |
break | |
print sum(primeDivs(x+1, primes)) |
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