Important: The numtheory package has been deprecated.  Use the superseding command NumberTheory[NextSafePrime] instead.

The function safeprime will compute the smallest safe prime that is greater than n. A safe prime is a number p such that p is prime and $\frac{\left(p-1\right)}{2}$ is prime.

The command with(numtheory,safeprime) allows the use of the abbreviated form of this command.

$\mathrm{with}\left(\mathrm{numtheory}\right)\:$

$\mathrm{safeprime}\left(8\right)$

$11$

$\mathrm{safeprime}\left(12\right)$

$23$