HP 40gs User Manual page 232

ISPRIME?
LCM
MOD
14-50
IREMAINDER works with integers and with Gaussian
integers. This is what distinguishes it from MOD.
Example 2
Typing:
IREMAINDER(2 + 3·i, 1 + i)
gives:
i
Returns a value indicating whether an integer is a prime
number. ISPRIME?(n) returns 1 (TRUE) if n is a prime or
pseudo-prime, and 0 (FALSE) if n is not prime.
Definition: For numbers less than 10
and prime mean the same thing. For numbers greater
14
than 10 , a pseudo-prime is a number with a large
probability of being prime.
Example 1
Typing:
ISPRIME?(13)
gives:
1.
Example 2
Typing:
ISPRIME?(14)
gives:
0.
Returns the least common multiple of two integers.
Example
Typing:
LCM(18, 15)
gives:
90
See "MOD" on page 13-15.
14
, pseudo-prime
Computer Algebra System (CAS)