24 lines
485 B
Python
24 lines
485 B
Python
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#!/usr/bin/env python3
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def fst_layer(a, b, c):
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return 2*(a*b + a*c + b*c)
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def abc(n):
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for a in range(1, int((n//6)**0.5)+1):
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for b in range(a, int((a**2 + n//2)**0.5) - a):
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for c in range(b, (n - 2*a*b) // (2*a + 2*b)):
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yield a,b,c
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n = 2*10**4
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sieve = [0]*n
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for a,b,c in abc(n):
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m = 0
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lyn = fst_layer(a, b, c)
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while lyn < n:
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sieve[lyn] += 1
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lyn += 4*(2*m + a + b + c)
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m += 1
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print(sieve.index(1000))
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