Пример #1
0
def is_strong_harshad(n):
    """ Determine if n / (sum of digits of n) is prime

    :param n:
    :return:
    """
    sum_digits = euler.sum_digits(n)
    return n % sum_digits == 0 and euler.is_prime(n / sum_digits)
Пример #2
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def solve(max_value):
    strong_right_truncatable_harshad_primes = []
    for right_truncatable in right_truncatable_generator():
        # for each right truncatable number, figure out if it is strong,
        # prime. If so add to sum
        if is_strong_harshad(right_truncatable):
            for new_digit in xrange(10):
                to_test = right_truncatable * 10 + new_digit
                if euler.is_prime(to_test):
                    strong_right_truncatable_harshad_primes.append(to_test)
                if to_test > max_value:
                    return sum(strong_right_truncatable_harshad_primes)
    return sum(strong_right_truncatable_harshad_primes)