Online calculator to calculate the sum of the first n terms and the nth term of an arithmetic sequence.

If A1, A2, ... , An, ... is an arithmetic sequence with common difference d, this calculator calculates the sum Sn given by

How to use the calculator

1 - Enter the first term A1 in the sequence, the common difference d and n the number of terms in the sum then press enter. An example is shown where a₁ and d may entered as integers, decimals or fractions and n must be a positive integer.