On 1/7/2013 8:38 AM, djbroadhurst wrote:
> David Cleaver wrote:
> > Pari/GP has a function called znprimroot()
> Which works perfectly, with
> > GP/PARI CALCULATOR Version 2.5.0 (released)
> if you will read the friendly manual:
> > znprimroot(n): returns a primitive root of n when it exists.
I have just downloaded version 2.5.3, which also says:
znprimroot(n): returns a primitive root of n when it exists.
What I was trying to convey is that Pari/GP can also return what looks like a
valid answer, even though the input does not have a primitive root, ie:
%1 = Mod(2, 15)
%2 = Mod(17, 30)
%3 = Mod(5, 33)
%4 = Mod(2, 91)
I have read the fine/friendly manual, ie ?znprimroot. However, this says
nothing about what happens when the primitive root does not exist. I have found
several places online that do discuss that the result in those situations will
be "undefined", like here:
However, I believe we are in complete agreement that when you want a primitive
root of numbers that have (at least) one, then you can use the znprimroot()
function in Pari/GP to find it.