1. ## How to solve this three-variable quadratic Diophantine equation?

I have the following quadratic diophantine of three variables: (4x^2 + 1 )( 4y^2 + 1 ) = (4z^2 + 1) but cannot find a good algorithm or method for finding solutions. Any advice would be appreciated.

2. ## Re: How to solve this three-variable quadratic Diophantine equation?

Maybe you should try these replacements: $4x^2+1=a$ and $4y^2+1=b$.