Re: eulerphi(0)

[John Cremona <john.cremona@gmail.com>]

I cannot think of anyone wanting to evaluate eulerphi at 0, but one
reason for the answer 2 is that it is exactly the number of units in
Z/nZ when n=0!

John

On 14 September 2017 at 20:46, Max Alekseyev <maxale@gmail.com> wrote:
> Is there any particular reason behind eulerphi(0) = 2 ?
>
> ? eulerphi(0)
> %1 = 2
>
> I'd rather expect eulerphi(0) to result in an error.
> Zero value would also make more sense, since there are no positive integers
> <=0 (even if we do not care about co-primality).
>
> Regards,
> Max