Geometric Sequence
Find the nth term and finite sum with an editable common ratio.
Your numbers
Nth term
Use consistent units. The result follows the assumptions you enter.
Scenario comparison
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Formula
aₙ=a₁r^(n−1); Sₙ=a₁(1−rⁿ)/(1−r), with r=1 handled separately.
Find the nth term and finite sum with an editable common ratio.
Worked example
- First term
- 2
- Common ratio
- 3
- Number of terms
- 5
- Nth term
- 162
- Finite sum
- 242
Scope and limitations
Use consistent units. The result follows the assumptions you enter.
Inputs are checked for missing values and allowed ranges. A result outside the finite numeric range is not displayed. Rounding affects display, while the calculation uses the model’s numeric precision.
Check your units and assumptions before relying on a result. Changing a label does not convert a currency or physical unit.
Formula version: 34de3ad956ea · Example checked: