c+CalcLantern

Geometric series sum

Sum a finite geometric series and check its infinite limit.

How this works

Sₙ = a(1 − rⁿ)/(1 − r); for |r| < 1, S∞ = a/(1 − r).

Example

Using the example inputs, finite sum is 1.875.

First term
1
Common ratio
0.5
Number of terms
4
Finite sum
1.875

Scope and assumptions

Uses your inputs only; results are rounded for display.

OpenStax mathematics

Related calculators

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Arithmetic sequence term

Geometric sequence term

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