|16||Progressions, Permutations, and Combinations|
Whatever system you use in arithmetic or algebra, a sequence of numbers can reveal a pattern that will help you to develop and check that sequence in various ways. Such a pattern is unlike the ones in multiplication tables. They depend on the system or notation that was used: decimal, octal, hexadecimal, binary, or whatever. Sequence patterns exist independently of the numbering base.
Five arithmetic progressions are listed below. Four are specific, and the fifth is general. First is the counting number sequence itself. Second is the even numbers. (Odd numbers would be similar, but starting with 1 and adding 2 for each successive number.) Third is the numbers divisible ...