PROJECT EULER · #0422
Sequence of Points on a Hyperbola
Let
Next, define
Now we define a sequence of points in
-
. -
. - For
, is the unique point in that is different from and such that line is parallel to line . It can be shown that is well-defined, and that its coordinates are always rational.

You are given that
Find
If
For
Write-up coming later
The complete problem is available here. An approach, code, and answer will be added later.