sigma summation to a range

Joseph Stavitsky wrote: Let's say I define a vector variable and then I want to do sigma summation for every element, from 1 to the element. Can I do this? Or perhaps with a range variable?

In addition to Alan's method, you might want to consider using the summation operators (in Mathcad 15, there's the Summation operator in the Calculus toolbar and the Vector Summation operator in the Matrix toolbar; In Prime, there's just one summation operator which allows you to either write the specific range or, by leaving the summation placeholders blank, sum over the entire vector).

Stuart