Calculate the Chessboard Problem

Calculator for the chessboard problem, which determines the number of grains at a doubling or other multiplication rate per square. The chessboard problem originates from an arab legend, after which the inventor of the chess game was granted a wish. He wished for one grain of wheat on the first square of the chessboard, two on the second, four on the third and so on, twice the amount on each further square. Which at first doesn't seem much, would be more than 18 quintillion grains of wheat or more than 700 gigatons, much more than there is on Earth.
Here, for any amount of squares (at a chessboard 64), for any multiplication factor (at the original chessboard problem 2) and any start value (usually 1), the number of grains per square and in total can be calculated.