is trivial to solve by taking and . is more difficult, but can be solved by noting that solutions
exist iff can be written as a sum of two squares
of nonnegative integers. The first such values
of
are 1, 2, 4, 5, 8, 9, 10, 13, 16, 17, 18, 20, 25, 26, ... (OEIS A001481).
, 
, 
, and 
, with 
a fixed positive integer
parameter and trivial solutions having 
, 
, or 
excluded.
is trivial to solve by taking 
and 
. 
is more difficult, but can be solved by noting that solutions
exist iff 
can be written as a sum of two squares
of nonnegative integers. The first such values
of 
are 1, 2, 4, 5, 8, 9, 10, 13, 16, 17, 18, 20, 25, 26, ... (OEIS A001481).
