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Topic: Pell type equations
Replies: 29   Last Post: Apr 29, 2012 5:37 PM

 Messages: [ Previous | Next ]
 Terry M Posts: 15 Registered: 4/26/12
Re: Pell type equations
Posted: Apr 29, 2012 6:07 AM

"Helmut Richter" <hhr-m@web.de> wrote in message
> On Sat, 28 Apr 2012, Terry M wrote:

> e.g. 3x² + 7y² is never 6 (mod 8).

Hi Helmut,

The more I reread your posts, the more I'm getting confused :(

possible values of 3x² (Mod 8) are 0, 3 and 4
possible values of 7y² (Mod 8) are 0, 4 and 7

so 3x² + 7y² can only be 0, 3, 4 or 7 (Mod 8)

so 3x² + 7y² is never 1, 2, 5 or 6 (Mod 8)

I think I'm correct in this ?
> Helmut Richter

Date Subject Author
4/26/12 Terry M
4/26/12 Dan Cass
4/26/12 Dan Cass
4/26/12 bert
4/26/12 Terry M
4/26/12 amzoti
4/26/12 Timothy Murphy
4/27/12 Terry M
4/27/12 Helmut Richter
4/27/12 Terry M
4/28/12 Helmut Richter
4/28/12 Terry M
4/28/12 Helmut Richter
4/28/12 Terry M
4/28/12 Terry M
4/28/12 Helmut Richter
4/28/12 Terry M
4/29/12 Terry M
4/29/12 Terry M
4/29/12 Helmut Richter
4/29/12 Terry M
4/29/12 Terry M
4/29/12 Terry M
4/28/12 Timothy Murphy
4/28/12 Terry M
4/28/12 Helmut Richter
4/28/12 Terry M
4/29/12 Timothy Murphy
4/29/12 Helmut Richter
4/29/12 Timothy Murphy