wu :: forums
        (http://www.ocf.berkeley.edu/~wwu/cgi-bin/yabb/YaBB.cgi)
      

        riddles >> medium >> quadruple
        
(Message started by: Christine on Sep 15th, 2013, 4:56pm)
Title: quadruple
Post by Christine on Sep 15th, 2013, 4:56pm
Diophantus quadruple (1/16, 33/16, 17/4, 105/16)

the product of any two distinct terms + 1 is a square

How can you find other sets of rational quadruple?
Title: Re: quadruple
Post by SEMfuze on Sep 27th, 2013, 7:20am
y
2 = (a1x + n)(a2x + n)(a3x + n)(a4x + n)(a5x + n)
Title: Re: quadruple
Post by Christine on Sep 27th, 2013, 9:40am

on 09/27/13 at 07:20:19, SEMfuze wrote:
y
2 = (a1x + n)(a2x + n)(a3x + n)(a4x + n)(a5x + n)


It doesn't look right. Maybe I miss something here.
Please clarify.
Title: Re: quadruple
Post by towr on Sep 27th, 2013, 2:35pm
I think he meant to copy/paste the formula for a hyperelliptic curve y2 = (a1x + 1)(a2x + 1)(a3x + n)(a4x + 1)(a5x + 1)  (n=1 in this case). Equation 2 on page 2 of http://arxiv.org/pdf/math/0002088.pdf, for example (I haven't read it, and not sure how much I'd understand of it if I would).
Title: Re: quadruple
Post by Christine on Sep 27th, 2013, 5:15pm

on 09/27/13 at 14:35:19, towr wrote:
I think he meant to copy/paste the formula for a hyperelliptic curve y2 = (a1x + 1)(a2x + 1)(a3x + n)(a4x + 1)(a5x + 1)  (n=1 in this case). Equation 2 on page 2 of http://arxiv.org/pdf/math/0002088.pdf, for example (I haven't read it, and not sure how much I'd understand of it if I would).


Ouch! Thanks. The stuff on arxiv  is tough to understand. The question I posted is more difficult than I anticipated.


Powered by YaBB 1 Gold - SP 1.4!
Forum software copyright © 2000-2004 Yet another Bulletin Board