Support nCr and nPr
Some stochastic functions that may be useful are missing. E.g. the ones mostly known from (hardware) calculators, i.e. nCr
and nPr
.
What happens
If I enter 9 nCr 5
I get "Unknown variable nCr".
What should happen
If I enter 9 nCr 5
I want to get 126 as a result.
More information
Calculation should be known, but just for reference: https://math.stackexchange.com/a/429495