Arithmetic Sequence Calculator
Use the Arithmetic Sequence Calculator for a transparent, instant calculation with validated inputs and cited sources. For a query such as “arithmetic sequence”, enter the matching values and units below and review the stated assumptions. The same model applies to the related search “arithmetic sequence formula” only when it uses the displayed inputs and assumptions.
How to use this calculator
Enter the requested values and units.
Review the assumptions and any warnings shown with the result.
Use the result together with the cited source and your real-world requirements.
Formula
The nth arithmetic term is aₙ = a₁ + (n − 1)d; the sum through n is n × [2a₁ + (n − 1)d] ÷ 2.
Worked example
Worked example: Inputs: First term: 2; Common difference: 3; Term number: 10. Outputs: Nth term: 29; Sum through nth term: 155.
Assumptions and limits
- The result depends on the values, units, and assumptions entered. It does not infer missing context.
Sources
- OpenStax, Rice University: Precalculus 2eReference material reviewed for the stated method, units, or domain. Confirm that its scope matches your use case. Reviewed 2026-08-14.
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Frequently asked questions
How does the Arithmetic Sequence Calculator work?
The nth arithmetic term is aₙ = a₁ + (n − 1)d; the sum through n is n × [2a₁ + (n − 1)d] ÷ 2.
What should I enter?
First term, Common difference, Term number
What should I verify?
Review the assumptions and any warnings shown with the result. The result depends on the values, units, and assumptions entered. It does not infer missing context.
Last updated 2026-08-14 · math-arithmetic-sequence-v1 · opportunity-content-2026-08-14 · Trusty Calculator Editorial Team