Sequential Number Column - How do I set it as key without a formula incrementally adding by one?

[ekk20]

I understand that there will be complication if the app has multi-user. However, the app I’m creating is only used by only myself, also I’ve been using sequential numbers in the past so migrating to using this app it is essential I continue to do so.

I’m wondering how I could set the sequential number column as key? Having a formula that generates the sequential key prevents me from doing that in either appsheet or google sheet.

Thank you