Question 1176441
{{{(x^-2+x^-1)^3}}}

{{{(1^""/x^2+1^""/x^"")^3}}}

That has no negative indices (We only called them 'exponents' in the olden days,
and 'index' (plural 'indices') referred to n for the nth root).

You can go further and get

{{{(x + 1)^3/x^6}}} if you like.

Edwin<pre>