Brightness difference 1 dice(single), 2 die(dual), 3 die (trie) on a tri cree

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Can anyone estimate the brightness difference between using a single, dual, and tri cree full powah setup? Lets say they are all BBB.
I noticed you can really tell a difference between 1 die and 2 die.
Using a lux meter app on my phone I got the following results
The brightness for the single die got up to 1600
The brightness for the dual dice got up to 3800 and you can tell it is definitely brighter.
I put the phone's light sensor near the blade closest to the LED.
The difference between 1 and 2 die is definitely dramatic. I would say at least twice as bright according to my lux meter and eyes.
Is the difference between 2 and 3 die as dramatic? Can you tell a big difference between using 2 die and 3 die?