29 lines
780 B
Python
29 lines
780 B
Python
from lib_misc import sum_proper_divisors
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def is_abundant(n):
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return sum_proper_divisors(n) > n
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def is_sum_of_two_abundant(n, abundant_numbers, abundant_numbers_set):
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for a in abundant_numbers:
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if a > n:
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return False
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d = n - a
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if d in abundant_numbers_set:
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return True
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return False
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def euler_023():
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abundant_numbers = [n for n in range(1, 28123 + 1) if is_abundant(n)]
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abundant_numbers_set = set(abundant_numbers)
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return sum([n for n in range(1, 28123 + 1)
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if not is_sum_of_two_abundant(n, abundant_numbers,
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abundant_numbers_set)])
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if __name__ == "__main__":
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print("e023.py: {}".format(euler_023()))
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assert(euler_023() == 4179871)
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