Returns the number of combinations[1][2] of n unlike things taken k at a time.
Syntax:
COMBIN( n:Number, k:Number )
This function yields the number of combinations of n unlike things taken k at a time.
Formula:
nCk = n! ∕ ((n − k)! × k!)
For very large n an approximation is achieved using logarithms.
Revisions:
This function was added in 1.30.