Definition:Arithmetic Sequence

Definition
An arithmetic progression is a finite sequence $\left \langle{a_k}\right \rangle$ in $\R$ defined as:
 * $a_k = a_0 + k d$ for $k = 0, 1, 2, \ldots, n - 1$

Thus its general form is:
 * $a_0, a_0 + d, a_0 + 2 d, a_0 + 3 d, \ldots, a_0 + \left({n - 1}\right) d$

Also known as
The term arithmetical progression is sometimes seen.

Also see

 * Sum of Arithmetic Progression
 * Definition:Arithmetic Series

Linguistic Note
In this context, the word arithmetic is pronounced with the stress on the first and third syllables: a-rith-me-tic, rather than on the second syllable: a-rith-me-tic.

This is because the word is being used in its adjectival form.