Euler summation

Euler summation is a way of adding a lot of numbers together very quickly. It's named after a mathematician called Leonhard Euler.

To understand Euler summation, think about how you would add up a giant stack of numbers. You likely would start at the bottom and work your way up, adding each number to the one before it until you get to the top. That is one way of adding a lot of numbers, but it takes a long time.

Euler summation is a faster way of adding a lot of numbers together. Imagine that stack of numbers again, except this time you start at the top and work your way down. With Euler summation, you keep track of how much information you are losing as you go down the stack by subtracting the smallest numbers first. This means you can add the biggest numbers together first, and you don't need to worry about the small numbers as much.

Overall, Euler summation is a quick way of adding a bunch of numbers together that was invented by Leonhard Euler. It helps you work your way down a stack of numbers faster by subtracting the smallest numbers first and adding the bigger ones together first.