Retaining number sequence

Hello,

I have a set of sound files for live music performance. I want to number them 1-800 for example. I would like each file to always have the same number. Sometimes I delete a sound sample. Sometimes I add samples. Is there a way to use advanced renamed to maintain the sequence and also "fill in gaps" created by deleted files with new files before extending the existing number sequence. Numbering of existing files must never change.

Thank you

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