Arithmetic Sequence Calculator
Find the nth term and the sum of the first n terms of an arithmetic sequence from the first term and common difference.
- Sum of first 10 terms
- 155
Formula: aₙ = a₁ + (n − 1) × d
About Arithmetic Sequence Calculator
Arithmetic Sequence Calculator is a free online calculator that gives you an instant, accurate result as you type. Find the nth term and the sum of the first n terms of an arithmetic sequence from the first term and common difference.
The calculation uses the standard formula aₙ = a₁ + (n − 1) × d and updates live with every change to the inputs. Everything runs client-side in your browser — fast, private, and free to use as often as you like.
Legend says young Gauss summed 1 to 100 instantly by pairing terms — the same n(a₁+aₙ)/2 idea behind the arithmetic series formula.
Frequently Asked Questions
Is Arithmetic Sequence Calculator free to use?
Yes. Arithmetic Sequence Calculator is completely free, with no sign-up, no downloads, and no usage limits. You can use it as many times as you like on any device with a web browser.
How accurate is this calculator?
The calculator applies the standard formula (aₙ = a₁ + (n − 1) × d) with full floating-point precision and rounds only the displayed result. For most practical purposes the results are exact.
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