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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