I would like to leave feedback about this task.

It's not take so much time for resolving this kata using separate factorial function, however JavaScript tests are failed if n>=171(Reasen: Infinity).

In my opinion it's logically correct to use factorial function because it's described in additional information in this task(Calculation of binomial coefficient).
And for me It took much time to resolve this task without factorial function.

So my thought is: it would be good to have this notes(for JS, TypeScript) in task description or fix tests to work with this solution(using factorial) as well.

I'm not aware of this. Thanks for explanation.

I'm not sure but in my opinion this Kata is not for level 7 kyu. It might be level 6 kyu.

Description is not clear in part of "The number of cards will vary, but will never be more than 7 (the board (5) + player hand (2))".
This Kata is not for level 7kuy definitely. Probably for 6kuy.

Could someone explain what is the problem with next test:
Testing n: 2, array: [6,3,1,7,5,4]
✘ expected:<15> but was:<14>
My result is: 14, 3+7+4=14 but test shows expected 15?