Arithmetic and Geometric Sequences and Series Solver

A program that will identify and then solve Arithmetic and Geometric Sequences and Series
after the user inputs the first three terms, a desired unknown term to be calculated,
and a starting and ending term for finding the sum of the related series.

The Arithmetic Sequence and Series Formulas used are:

• a_n = a₁ + (n -1)*d where d = common difference
• S_n = (n/2)(a₁ + a_n)

The Geometric Sequence and Series Formulas used are:

• a_n = a₁ * r^n-1 where r = common ratio
• S_n = a₁ * (1-rⁿ)/(1-r)
• S_∞ = a₁ * (1)/(1-r), where -1<r<1

This program is written in JavaScript.

By Mr. C. July 18, 2015