Python math - comb() Function

The Python math.comb() function returns the number of ways to choose k items from n items without repetition and without order. It is also known as combinations and mathematically can be expressed as:

Where k ≤ n. If k > n, the function returns zero.

Syntax

#New in version 3.8
math.comb(n, k)   

Parameters

Return Value

Returns the number of ways to choose k items from n items without repetition and without order.

Exceptions

• Throws TypeError if either of the arguments are not integers.
• Throws ValueError if either of the arguments are negative.

Example:

The example below shows the usage of comb() function.

import math

#choosing 2 items from 3 items
#without repetition and without order
print(math.comb(3, 2))

#choosing 5 items from 10 items
#without repetition and without order
print(math.comb(10, 5))

The output of the above code will be:

3
252