I believe the multiples of prime numbers will be the answer.
Like 11,13,17,19 are prime numbers that are not the factors of 10!
So multiplying them with 2 should give us non primes.
11x2-22 (1st)
13x2-26 (2nd)
17x2-34 (3rd)
19x2-38
but when I try 34 as the answer, it is wrong. Can anyone help me with this question?
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