Sigma function - big numbers

[Décio Luiz Gazzoni Filho]

On Dec 18, 2007, at 11:03 PM, Paroxyzm wrote:

> Hi!
>
> I'm new to GMP....
>
> I cannot find any documentation relating to sigma function.
>
>
> The sigma function is a  sum of all devisors of number n.
>
> Example:
>    sigma(2)= 1+2 =3
>    sigma(3)= 1+3 =4
>    sigma(4)= 1+2+4 =7
>    sigma(6)= 1+2+3 =7
> etc...
>
> Can anyone tell me where can I find it??

GMP is not a number theoretical library, although it does have some  
number theory related functions. You're better off looking at PARI or  
NTL. The GP calculator from PARI does have the sigma function, I just  
checked, so PARI itself should have as well.

Décio