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[Darren_Murphy]

What are all formula you can use with math?

Yes, there is a solution - templates. Create a template column that concatenates the customer name and product, then relate that template column to itself. Then do a rollup through that relation to get a count. This is bread and butter stuff when it comes to Glide computed columns. Dig out a few of Bob Petitto’s tutorials and watch them. He covers this sort of stuff in many/most of them.