Arithmetic Sequence Calculator

Calculate arithmetic sequence terms and sums. Free online arithmetic progression calculator.

The Arithmetic Sequence Calculator finds any term and the sum of terms in an arithmetic progression where each term differs by a constant amount. Enter the first term and common difference to generate terms, find the nth term, or calculate the sum of the first n terms. Essential for pattern recognition, financial planning, and mathematical studies.

Common use cases

  • Predicting salary growth
  • Stadium seating calculations
  • Loan payment schedules
  • Pattern recognition problems
  • Distance with constant speed change

How to use

  1. Enter the first term (a₁)
  2. Enter the common difference (d)
  3. Specify which term or sum to calculate
  4. Click calculate for results
  5. View the sequence terms

FAQ

What is an arithmetic sequence?

A sequence where each term equals the previous term plus a constant (common difference). Example: 2, 5, 8, 11... (d=3).

What is the nth term formula?

aₙ = a₁ + (n-1)d, where a₁ is first term, d is common difference, n is term number.

How do I find the sum of n terms?

Sₙ = n(a₁ + aₙ)/2 = n(2a₁ + (n-1)d)/2.

Can the common difference be negative?

Yes, negative common difference creates a decreasing sequence like 20, 15, 10, 5...