The Sigma notation means "sum up". Essentially, we just add together everything after the Sigma symbol. Let's take this: $latex \sum\limits_{n=1}^5n &s=4$ You have n after the Sigma, but how to you "sum up" n? Well, if we take a look under the Sigma symbol we see n=1 and if we look above the Sigma we see 5. This … Continue reading Maths for Developers: Sigma