Skip to content
Free public beta until December 4, 2026: every course is open, no card needed. After that, the first chapter of each course stays free and full access is a one-time $39 ($19 for up to 100 founding members chosen for helpful feedback). Your progress is kept. How the beta works

arithmetic sequence

A list of numbers where each term is the last one plus a fixed common difference.

A sequence is arithmetic if consecutive terms always differ by the same constant d, the common difference: a_n = a_{n-1}+d. Its explicit formula is a_n = a_1+(n-1)d, and graphed against n its terms lie on a straight line of slope d.

Read the full section →
Graph settings

Calculator