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Is there a name for numbers whose factors only consist of prime numbers but are not prime in themselves? (lemmy.world)

submitted 1 year ago by favrion@lemmy.world to c/math@lemmy.world

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For example, 22 has factors of 2 and 11, both prime numbers, yet 22 itself is not prime.

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[–] palebluethought@lemmy.world 3 points 1 year ago

This would be true if and only if the number has exactly 2 prime factors. Otherwise, if n = abc, then a*b (or any other choice of two) is also a factor, and is not prime.