19 lines
405 B
Python
19 lines
405 B
Python
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#!/usr/bin/env python3
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def divisors(n):
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sieve = [1]*n
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for p in range(2, n):
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if sieve[p] > 1:
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continue
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pw = 1
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while p**pw < n:
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for i in range(p**pw, n, p**pw):
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sieve[i] *= (pw+1)
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sieve[i] //= pw
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pw += 1
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return sieve
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n = 10**6 // 4
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divs = divisors(n+1)
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print(len([0 for i in divs if 0 < i//2 <= 10]))
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