8. Which positive integers have exactly
a) two positive divisors
b) three positive divisors
c) four positive divisors?
Solutions — 2
Solution 1
8. a) primes
b) squares of primes primes
c) products to two distinct primes or cubes of
Solution 2
8. a) primes
b) squares of prime primes
c) products of two distinct primes or cubes of
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