Hi @Revel 
Formula approach won’t help much here since it is more suitable for getting the total of uniques who performed those 3 events individually rather than uniques users who performed all 3 events.

e.g this demo chart - https://analytics.amplitude.com/demo/chart/new/srqy32n

Per the formula in the chart, you will get the daily arithmetic sum of uniques performing the 3 events separately.

If you want to get unique user count who have performed all three specific events over a given time frame, then a segment or cohort approach will be helpful.

eg. this chart - https://analytics.amplitude.com/demo/chart/new/9mdth0m. In this chart, you get your unique count of users who did all those 3 events during the last 30 days.

Make sure you are using the same time frame for each of the performed clauses as results may differ accordingly.

Hope this helps.

Thanks!