39 lines
779 B
Python
39 lines
779 B
Python
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def primes(n):
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""" Nice way to calculate primes. Should be fast. """
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l = range(2, n + 1)
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_l = []
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while True:
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p = l[0]
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if p * p > n:
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return _l + l
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l = [i for i in l if i % p != 0]
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_l.append(p)
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def produce_prime(a, b, n, primes):
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x = n*n + a*n + b
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return x in primes
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def f_027():
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""" n^2 + a*n + b
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1) b must be prime
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"""
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p6 = set(primes(1000000))
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p3 = primes(1000)
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options = [(a, b)
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for a in range(1, 1000, 2)
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for b in p3]
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print(len(options))
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for n in range(100):
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options = [(a, b)
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for a, b in options
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if produce_prime(a, b, n, p6)]
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print(options)
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print(len(options))
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f_027()
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