41 lines
1.0 KiB
Python
41 lines
1.0 KiB
Python
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import math
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def get_proper_divisors(n):
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proper_divisors = set([1])
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for i in range(2, int(math.sqrt(n)) + 1):
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if n % i == 0:
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proper_divisors.add(i)
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proper_divisors.add(n / i)
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return proper_divisors
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def is_abundant(n):
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return sum(get_proper_divisors(n)) > n
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def get_abundant_numbers_smaller(n):
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ret = []
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for i in range(1, n):
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if is_abundant(i):
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ret.append(i)
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return ret
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def is_sum_of_two_abundant(n, abundant_numbers):
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abundant_numbers_set = set(abundant_numbers)
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for a1 in abundant_numbers:
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if a1 > n:
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return False
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elif (n - a1) in abundant_numbers_set:
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return True
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if __name__ == "__main__":
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abundant_numbers = get_abundant_numbers_smaller(30000)
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cannot_be_written_as_sum_of_abundant = []
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for i in range(28129):
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if not is_sum_of_two_abundant(i, abundant_numbers):
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cannot_be_written_as_sum_of_abundant.append(i)
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print(sum(cannot_be_written_as_sum_of_abundant))
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