How to run an expression in CAS mode in program

[Arno K]

There once was a thread concerning MOD, you perhaos should look at :

(08-21-2015 11:09 AM)parisse Wrote:  MOD was implemented inside the CAS for the first version of the 39GII, it was not meant to be used with exact data, the CAS function for integer remainder is irem, and here the right function is powmod(7,23,143) because computing 7^23 before doing remaindering is much much less efficient.
I will add integer checking for arguments inside MOD.

which here then can be used : powmod(a,n-1,n)
Arno