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Arithmetic Sequence Calculator

Calculate the nth term and the sum of the first n terms of an arithmetic sequence.

 

 

 

aₙ
Sum

About this calculator

Use this calculator for a sequence with a constant difference d: 3, 8, 13, 18, … The nth term is aₙ = a₁ + (n − 1) d. The sum of the first n terms is Sₙ = n/2 × (a₁ + aₙ).

n must be a positive integer (at least 1). d may be negative (a decreasing sequence) or zero (a constant sequence).

First term a₁: The first term.

Common difference d: Amount added each step.

n: Which term and how many terms to sum (n ≥ 1).

aₙ: The nth term.

Sum: Sₙ, the sum of the first n terms.