Arithmetic Sequence Calculator

How to use this tool

1. Enter the first term, the common difference and n. The difference may be negative for a decreasing sequence.
2. Press Generate. You get the nth term, the sum of the first n terms, and every term in between.
3. Use Load sample for 3, 7, 11, 15, 19, or Clear to start again.

Worked example

With first term 3, difference 4 and n = 5, the sequence is 3, 7, 11, 15, 19. The 5th term is 19 and the sum is 55, since 5 / 2 x (2 x 3 + 4 x 4) = 55.

What this tool does not do / Limits

This tool handles arithmetic sequences only (a constant difference). It does not handle geometric sequences, and it caps the listing at 200 terms so the page stays readable; the nth term and sum still use the exact formulas.

Frequently asked questions