Arithmetic Sequence Calculator
Find a term and partial sum of a constant-difference sequence.
Your inputs
Calculation results
Formula & assumptions
Term = a+(n−1)d; sum = n[2a+(n−1)d]/2.
Values use the specified units. Calculations use floating-point arithmetic. Check input measurements and formula assumptions before applying the result.
Compare your scenarios
Save up to five results to compare changes side by side. Scenarios stay in this tab until you clear or reload it.
Using Arithmetic Sequence Calculator
Find a term and partial sum of a constant-difference sequence.
- Enter first term, common difference, term number using the units printed under each field.
- Choose Calculate, or enable live updates. Review the result labels and formula assumptions.
- Save scenarios to compare up to five variations, then copy the report or download JSON or CSV.
Example
First term: 3 units Common difference: 4 units Term number: 10 terms Selected term: 39 Sum through term: 210
Questions & answers
What does Arithmetic Sequence Calculator calculate?
Find a term and partial sum of a constant-difference sequence.
Which units should I enter?
First term uses units. Common difference uses units. Term number uses terms. Convert values to these units before calculating.
Which formula does it use?
Term = a+(n−1)d; sum = n[2a+(n−1)d]/2.
What does the included example show?
First term: 3 units; Common difference: 4 units; Term number: 10 terms. Result: Selected term = 39; Sum through term = 210.
Can I compare different settings?
Yes. Save a scenario, change the inputs and save another result. Up to five scenarios are compared in this tab; they disappear when you reload or leave.
Can I export the calculation?
Copy the JSON report or download JSON and CSV with inputs, result labels and numeric values. Processing uses local JavaScript; no calculation request is sent to our server. Displayed values use up to 10 significant digits; exports retain JavaScript numeric precision.
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