Problem

Source: APMO 1995

Tags: number theory, relatively prime, number theory unsolved



Let $a_1$, $a_2$, $\ldots$, $a_n$ be a sequence of integers with values between 2 and 1995 such that: (i) Any two of the $a_i$'s are relatively prime, (ii) Each $a_i$ is either a prime or a product of primes. Determine the smallest possible values of $n$ to make sure that the sequence will contain a prime number.