Identify Missing Numbers In Range

I'm trying to create a list of missing numbers in a range, but I can't fiure out how to do it. The problem lies in that the range of numbers is in the middle of a larger number. ie. xxx-xx-0001-xx would be number 1, and xxx-xx-0500-xx would be number 500.

I need to scan multiple sheets containing these numbers, and produce a list of the numbers missing from that range.

Example:

Sheet1 has xxx-xx-0001-xx through xxx-xx-0009-xx, and xxx-xx-0018-xx through xxx-xx-0042-xx.

Sheet2 has xxx-xx-0053-xx through xxx-xx-0062-xx, and xxx-xx-0067-xx through xxx-xx-0072-xx.

Sheet3 needs to have a function that produces a list showing xxx-xx-0010-xx through xxx-xx-0017-xx, xxx-xx-0043-xx through xxx-xx-0052-xx, and xxx-xx-0063-xx through xxx-xx-0066-xx.

I need to be able to do this without VBA. The list doesn't necessarily have to have a different number per cell, it could even show them all on 1 cell if it's easier, but it would be more presentable if it was 1 number per cell in a row or column.