Math Calculators
Number Sequence Calculator
Find the nth term and sum of a sequence.
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About the Number Sequence Calculator
Analyze a number sequence in one step. Choose arithmetic (each term adds a common difference) or geometric (each term multiplies by a common ratio), enter the first term, the common difference or ratio, and the term number, and the calculator returns that term and the sum of the sequence up to it. It's a handy tool for algebra, finance, and pattern problems.
How to use the Number Sequence Calculator
- 01Enter your sequence type, first term, common difference or ratio, and term number.
- 02Read the result instantly — it recalculates as you type.
- 03Adjust the numbers to model different scenarios.
Frequently asked questions
Arithmetic vs geometric sequence?
Arithmetic adds a fixed amount each step (2, 5, 8, …); geometric multiplies by a fixed ratio (2, 6, 18, …). This tool handles both.
What is the nth term?
The value at position n. Arithmetic: a + (n−1)d. Geometric: a × r^(n−1). The tool also sums the terms.