### 2.6.16 Test of primality : `is_prime isprime isPrime`

`is_prime(n)` returns `1` (true) if `n` is prime and `0` (false) if `n` is not prime.
`isprime` returns `true` or `false`.
Use the command `pari("isprime",n,1)` to have a primality certificat (see the documentation PARI/GP with the menu `Aide->Manuels->PARI-GP`) and `pari("isprime",n,2)` to use the APRCL test.

Input :

`is_prime(100003)`

Output :

`1`

Input :

`isprime(100003)`

Output :

`true`

Input :

`is_prime(98569898989987)`

Output :

`1`

Input :

`is_prime(14)`

Output :

`0`

Input :

`isprime(14)`

Output :

`false`

Input :

`pari("isprime",9856989898997789789,1)`

This returns the coefficients giving the proof of primality by the p−1 Selfridge-Pocklington-Lehmer test :

`[[2,2,1],[19,2,1],[941,2,1],[1873,2,1],[94907,2,1]]`

Input :

`isprime(9856989898997789789)`

Output :

`true`