### Sum of Series in Javascript

The sum of a set of numbers can be calculated by adding all the numbers together. For example, if you have a set of numbers: a, b, c, the sum can be expressed as:a + b + c = sum

You can also use the Greek capital letter sigma (Î£) to represent the sum of a set of numbers. The sum of a set of numbers from i=1 to n can be written as:

Î£ (i=1 to n) = a1 + a2 + a3 + ... + an

This notation is commonly used in mathematics and engineering to represent the sum of a series or sequence of numbers. The value of i represents the index of the terms being added and n is the number of terms in the series.