Nth Term of a Geometric Sequence Calculator
🔁 Sequences & series. Use the nth term of a geometric sequence formula to find nth term, first term a, common ratio r, term number n: pick the value you want, type the others, and the answer updates as you go.
Pick the ○ next to the value you want to find, fill in the others, and it solves as you type.
What each letter means
| Quantity | Unit |
|---|---|
| nth term | no unit |
| First term a | no unit |
| Common ratio r | no unit |
| Term number n | no unit |
Worked example
Find the nth term when First term a = 3, Common ratio r = 2, Term number n = 10.
Using an = a r^(n-1): nth term = 1536.
Frequently asked questions
What is the formula for nth term of a geometric sequence?
an = a r^(n-1).
What do the letters stand for, and what units are used?
nth term, First term a, Common ratio r, Term number n.
How do you calculate nth term?
Put the values into an = a r^(n-1). For example, with First term a = 3, Common ratio r = 2, Term number n = 10, nth term = 1536.
Can I solve for a different value?
Yes. In the calculator above, pick the circle next to any value (nth term, first term a, common ratio r, term number n) and fill in the others: it rearranges the formula for you.
