... From: William F Sindelar To: Sent: Friday, January 04, 2002 7:04 PM Subject: [PrimeNumbers] Is the

Message 1 of 5
, Jan 4, 2002

----- Original Message -----
From: "William F Sindelar" <w_sindelar@...>
To: <primenumbers@yahoogroups.com>
Sent: Friday, January 04, 2002 7:04 PM
Subject: [PrimeNumbers] Is the next one prime?

> Hi Everybody
> I don't have the programs that can manipulate huge integers so I'm
stuck
> and burning with curiosity. Can anyone calculate the next term in the
> following sequence and check to see if it is prime, and if it is, then
> calculate the next one and check it for primality etc. Here is the
> sequence:
> 3, 19, 419, 176819, 31265489219, ...next one (is it prime?)
> The sequence is generated by using the expression (N^2+3N+1). Starting
> with N=3 we calculate 19, and it being prime we substitute 19 for N
and
> calculate again to obtain 419, etc.

f(31265489219)=977530816197201697619 is composite

(=19*31*102181*526931*30824161)

> Another sequence starting with 29 is:
> 29, 929, 865829, 749662454729, ...

f(749662454729)=561993796032558961827629 is composite