The pairs are odd/even and prime/composite. For example, 9 is both odd and composite, whereas 2 is even and prime. (2 is the only even prime.)
However, 20=22*5 is composite because it has factors other than itself and one. It is also even, aka not odd, as it has a factor of 2.
15 and 9 are both odd, composite numbers less than 20.
4,6,8,9,10,12,14,15,16,18 :)
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15
9 and 15 are the only two odd composite numbers less than twenty.
9 and 15 only.
9 and 15
Oh, dude, you want the odd composite numbers less than 20? Alright, let me break it down for you. So, we've got 9, 15, and 21. Wait, no, scratch that last one, it's above 20. But yeah, those are the odd composite numbers you're looking for. Like, you're welcome.
there are infinity odd composite numbers
No, it is odd and prime.
15 is a composite number - it can be divided by 3 and 5. 11, 13, 17 and 19 are all prime numbers, not composite.
It is impossible to list the infinite number of composite odd numbers.