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gudnm/prime_rotations.py

Created August 23, 2016 22:25
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Project Euler problem #35
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prime_rotations.py
n = 1000000
primes = [False, False] + [True]*(n-2)
for i in range(2, int(n**0.5)+1):
if primes[i]:
primes[i*i::i] = [False] * len(primes[i*i::i])
def check_rotations(num):
s = str(num)
return all(primes[int((s+s)[i:i+len(s)])] for i in range(len(s)))
print(len([True for i in range(2, n) if (primes[i] and check_rotations(i))]))
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