34 lines
1.1 KiB
Python
34 lines
1.1 KiB
Python
from lib_prime import primes
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def find_max_series(start_index, series_list, series_set):
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""" Start at the given index and sum up consecutive primes
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into total. If a total is in the series_set (i.e. a prime) then
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store the current number of consecutive primes (length) and the total.
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If the total exceeds the last value of the given primes no longer
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sequence can be found. Return the max sequence length and total. """
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series_max = series_list[-1]
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total_max = 0
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total = 0
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for i in range(start_index, len(series_list)):
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total = total + series_list[i]
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if total in series_set:
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length = i - start_index + 1
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total_max = total
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if total > series_max:
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return (length, total_max)
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def euler_050():
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n_max = 1000000
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ps = primes(n_max)
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ps_set = set(ps)
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s = max([x for x in [find_max_series(i, ps, ps_set)
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for i in range(0, len(ps))] if x])
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return s[1]
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if __name__ == "__main__":
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print("e050.py: " + str(euler_050()))
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assert(euler_050() == 997651)
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