Primes (Problem $1$ )

Number Theory Level 1

Find the lowest prime $p_n$ such that $p_n \pm p_{n - 1}$ are also primes. If there's none, enter $0$

1 solution

Yajat Shamji
Sep 5, 2020

Since all primes are odd (except $2$ ):

$odd + odd = even$

Which means the only two primes left are $2, 3$ :

$3 + 2 = 5$

$3 - 2 = 1$

Since $1$ is not a prime, the answer is $\fbox 0$