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7.1.14  Testing primality

The is_prime, isprime and isPrime commands are tests for primality.

isprime and isPrime are the same as is_prime, except they return true or false.

Examples

is_prime(100003)
     
1           
isprime(100003)
     
true           
is_prime(98569898989987)
     
1           
is_prime(14)
     
0           
isprime(14)
     
false           

Use the command pari("isprime",n,1) (see Section 7.2.10) to get a primality certificate (see the documentation PARI/GP with the menu Help ▸ Manuals ▸ PARI-GP) and pari("isprime",n,2) to use the APRCL test.

Examples

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




    221
    1921
    94121
    187321




          

which are the coefficients giving the proof of primality by the p−1 Selfridge-Pocklington-Lehmer test.


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