Re: Demostration

*To*: mathgroup at smc.vnet.net*Subject*: [mg70446] Re: Demostration*From*: Peter Pein <petsie at dordos.net>*Date*: Mon, 16 Oct 2006 02:36:17 -0400 (EDT)*References*: <egsdu4$cp1$1@smc.vnet.net>

Erickson Paul-CPTP18 schrieb: > I guess this doesn't 'prove', but perhaps demonstrates: > > > Select[ Range[-100000,200000], IntegerQ[Sqrt[#^3+9]] &] > > {-2,0,3,6,40} > > There are 5 x values within a reasonable range. The ten (fine pairs) are > +/- due to the Sqrt for y. > > > You might choice a smaller range in order for faster execution ;-) You don't need to test for any integer x < -2, for example ;-) > > > > > -----Original Message----- > From: Miguel [mailto:mibelair at hotmail.com] To: mathgroup at smc.vnet.net > Subject: [mg70446] Demostration > > How canI to demostrate than the equation y^2=x^3+9 has 10 integer > solutions? > >