Isn't the left side bigger?

$\large { 4 }^{ x }+{ 5 }^{ y }={ 3 }^{ z }$

For non-negative integers $x,y,z$, let triplets $\left\{ { x }_{ 1 },{ y }_{ 1 },{ z }_{ 1 } \right\} ,\left\{ { x }_{ 2 },{ y }_{ 2 },{ z }_{ 2 } \right\} \ldots \left\{ { x }_{ n },{ y }_{ n },{ z }_{ n } \right\}$ be the solutions to the equation above,

Submit your answer as $\displaystyle \sum _{ i=1 }^{ n }( { { x }_{ i }+{ y }_{ i }+{ z }_{ i } } )$.