Sloppy wording, yes, bad example, not really. "just" requires you to consider "2...

detaro on April 28, 2019 | parent | context | favorite | on: Why isn't 1 a prime number?

Sloppy wording, yes, bad example, not really. "just" requires you to consider "2" to be the product of all numbers in the multiset {2}. Let "product of primes" mean "product of one or more primes" and it works.