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    OlympiadEasyNumber Theory5–6

    Sum of the Primes Below 20

    Soma dos Primos Menores que 20

    What is the sum of all prime numbers less than 20?

    Test each number from 2 to 19 in turn: it is prime when no number other than 1 and itself divides it.

    Solution

    Step 1 of 2

    1. 1.Primes less than 20: 2, 3, 5, 7, 11, 13, 17, 19