How many numbers n less than 100 have exactly one divisor other than 1 and n?
How many positive integers less than 2000 are of the form x^n for some positive integer x and n\ge 2?
Thank you so much if you answered!
How many numbers n less than 100 have exactly one divisor other than 1 and n?
n divsors
4 1 2 4
9 1 3 9
25 1 5 25
49 1 7 49
Notice Cphill's answers
they are ODD perfect squares except for 4, and ONLY prefect squares.
Answers like 81 won't work because it is a perfect power of 4 and 64 is a perfect cube.