Marking as resolved.

Here's a simple way to prove 88 cannot exist in the example you gave:

There is only one instance of a possible 88, but it's preceded by ...201. The number 201 is not valid because it is outside your range, the number 01 cannot work because a non-zero integer cannot start with 0, and it cannot be 1 because that is outside your range. Thus it is proven that [10,88] is not a valid solution.

is this what you're asking for? or should i also post my code so far as well?

([10, 88], '3713763283635660473566582375556524594843646862828033733842277941785331405274151281211069345120188439262230457167970162877501487571785724619491125364461865429') should equal [9, 87]