20, 40, 60, 80
The ones with less than three factors.
They all are prime numbers except 1
The three greatest whole numbers less than 200 that each have an odd number of factors are 144, 169 and 196.
By definition, a prime number has exactly two factors. So, there are no prime numbers with exactly three factors.
144, 121 and 100
14 (I think).
30, 42, 66, 70 and 78.
6, 8 and 10 are three out of 32 possible answers.
42 and its next three multiples.
4, 9, 25, and 49
4, 9, 25, 49
0, 1, 2, 3