ELI5: Explain Like I'm 5

Gaussian binomial coefficient

A gaussian binomial coefficient is a fancy way of counting the number of different ways you can choose a certain number of things from a larger group of things.

Let's say you have 10 toys and you want to pick 3 of them to play with. The gaussian binomial coefficient tells you how many different possible combinations of toys you could choose.

It's like you have 10 different colored marbles in a jar and you want to know how many ways you can pick 3 marbles out of the jar.

The formula for the gaussian binomial coefficient looks like this:

n choose k = (n!)/((k!) ((n-k)!))

Here, n is the total number of toys in your toy box or the number of marbles in your jar. k is the number of toys or marbles you want to choose.

The exclamation point (!) in the equation means you need to multiply a bunch of numbers together.

So, let's say you have 10 toys and you want to choose 3 of them.

The formula would be:
10 choose 3 = (10!)/((3!) ((10-3)!))
= (10x9x8x7x6x5x4x3x2x1)/((3x2x1) (7x6x5x4x3x2x1))
= 120

This means that there are 120 different possible combinations of toys you could choose if you have 10 and you want to choose 3.

In conclusion, the gaussian binomial coefficient is just a fancy formula that helps you count the total number of different combinations you can choose from a larger group of things.