28 lines
503 B
Python
28 lines
503 B
Python
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#!/usr/bin/env python3
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def add_divisors(n):
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for k in range(1, (len(sieve) - 1) // n):
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sieve[k*n] *= n * (sieve[k] // sieve[k*n])
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def primes(n):
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for p in range(3, int(n**0.5), 2):
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if sieve[p] != 1:
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continue
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for i in range(p**2, n, 2*p):
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sieve[i] = 0
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n = 10**5
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sieve = [1] * n
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add_divisors(2)
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add_divisors(5)
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primes(n)
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s = 0
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for p in range(7, n, 2):
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if sieve[p] == 1 and pow(10, sieve[p-1], 9*p) != 1:
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s += p
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print(s + 2 + 3 + 5)
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