I'm trying to figure out how to multiply a number by a sequence of numbers that is auto generated for each cell in a column.

Example:

A1: 40 * 1 = 40
A2: 40 * 2 = 80
A3: 40 * 3 = 120

Selecting the first two or three and pasting down just repeats those same numbers.

Is there an easy way to accomplish this task?

Thank you
Mike