How to use transpose unique filter function to make a comma separated list in a single cell?

by Rubin|Published March 1, 2024

I need help using transpose(unique(filter) to essentially filter only be unique ID’s and then convert the record number column into a list. I did this before and I showed the final result, but I forgot how to and I can’t replicate it. Is it possible for someone to figure out the way.

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