On the Solutions of the Exponential Diophantine Equation 3^x-n^y=2z^2
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Abstract
In this paper, we study the solutions of the exponential Diophantine equation , where
are non-negative integers and
is a positive integer. By using elementary properties of congruence and Leu and Li’s theorem, results are obtained that if
is even, then the equation has exactly four solutions, which are
, For some odd
, we show that if
, then the equation has non-negative integer solutions
in the form
,
,
and
, where
is a non-negative integer. This discovery provides the solutions in the case of
, namely, the solutions
of the equation in non-negative integers are given by
,
,
and
, where
is a non-negative integer. If
,
and the equation has a solution, then
is odd and
is even. If
,
and the equation has a solution, then
is even. Moreover, we prove that if
or
, then
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