12
The prime numbers and the squares of primes between 2 and 20: 3, 4, 5, 7, 9, 11, 13, 17 and 19.
11 13 17
The prime numbers between 10 and 20 are 11, 13, 17, and 19.
The prime numbers from 1 to 17 are 2, 3, 5, 7, 11, 13, and 17.
12
6
The prime numbers and the squares of primes between 2 and 20: 3, 4, 5, 7, 9, 11, 13, 17 and 19.
1, 2, 3, 4, 5, 7, 11, 13, 17, 19. (I think)
11 13 17
57
Both 11 and 17 are prime numbers.
ALL of the numbers between 1 and 100 are rectangular numbers, except for 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, and 97.
11, 13, 17, and 19
4, 6, 8, 9, 19
Rectangular numbers are a subset of composite numbers. The squares of prime numbers will be composite but not rectangular.
17 and 11 are prime numbers; the product of 17 and 11 is not.