Primes of form n^p+1

[f.firoozbakht at sci.ui.ac.ir]

Dear Hugo,

I recived the email of hv with the subject
  "Re: Primes of form n^p+1"
but my computer can not open the text so I don't know
what is the reply of hv.

Please note that if p is odd prime then n+1 divides n^p+1
so for p>2 and n>1 n^p+1 is composite also n-1 divides n^p-1
so n^p-1 for n>2 is composite and for n=2, the Merssene's
primes are of this form.

Regards,

Farideh

> SeqFans,
>
> http://mathworld.wolfram.com/Power.html
> <http://mathworld.wolfram.com/Power.html>  says:
> Very few numbers of the form n^p+-1 are prime.
> ... [snip primes of form n^p-1] ...
> The only prime numbers of the form n^p+1 for n<=100 and prime 2<=p<=10
> correspond to p=2 with n = 1, 2, 4, 6, 10, 14, 16, 20, 24, 26, ...
> http://www.research.att.com/projects/OEIS?Anum=A005574
> <http://www.research.att.com/projects/OEIS?Anum=A005574>
>
> I extended the search to even n<=10000 and prime p<=2099 using PFGW and
> didn't find any further primes of this form. Are there _any_ known other
> examples?
>
> Thanks
> Hugo
>
>
>




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