I think you're looking for a factorial number system [1] and/or Lehmer code [2]. [1] https://en.wikipedia.org/wiki/Factorial_number_system [2] https://en.wikipedia.org/wiki/Lehmer_code
For context, in the US there are 15.3 million students enrolled in high school, 3.7 million of which are expected to graduate this year (i.e. a little under a quarter, as one would expect) [1]. So the 2.2 million…
I think you're looking for a factorial number system [1] and/or Lehmer code [2]. [1] https://en.wikipedia.org/wiki/Factorial_number_system [2] https://en.wikipedia.org/wiki/Lehmer_code
For context, in the US there are 15.3 million students enrolled in high school, 3.7 million of which are expected to graduate this year (i.e. a little under a quarter, as one would expect) [1]. So the 2.2 million…