An ordered set of quantities
In math, a sequence is a list of numbers arranged in a specific order. Each number in the list is called a term, and there is usually a rule that tells us how to go from one term to the next.
For example, in the sequence 2, 4, 6, 8, 10, we’re adding 2 each time. That’s an example of an arithmetic sequence. In another example, 1, 2, 4, 8, 16, we’re multiplying by 2 each time. That’s an example of a geometric sequence.
Some sequences get longer forever (infinite), and some may stop after a certain number of terms (finite).
We use sequences in real life to:
- Track patterns (like growing savings or steps in a dance)
- Solve problems involving time and repeated actions
- Understand number patterns in algebra
When Do Students Learn About Sequences?
Students begin working with simple sequences in elementary school and go deeper into arithmetic and geometric sequences in middle and high school.
Grades 3–5 – Introduction to Sequences
Students identify number patterns and continue sequences using rules like “add 3” or “double the number.”
Grades 6+ – Working with Arithmetic and Geometric Sequences
Students use formulas to find specific terms and understand how sequences are used in algebra and real-world applications.
