Math

Recursive Sequence Calculator

Generate terms from aₙ = r·aₙ₋₁ + d, including Fibonacci-style rules.

Enter your values

ⓘ Live results

Results
nth term
301.546875
First terms
2, 6, 12, 21, 34.5, 54.75, 85.125, 130.688, 199.031, 301.547
Sum of all terms
846.640625
Long-run limit
Diverges (|r| ≥ 1)
Behaviour
Growing without bound

Quick answer

A linear recurrence aₙ = r·aₙ₋₁ + d builds each term from the last; it converges to d ÷ (1 − r) when |r| < 1.

aₙ = r·aₙ₋₁ + d

How to use the Recursive Sequence Calculator

  1. 1Enter the starting term.
  2. 2Enter the multiplier and the constant added each step.
  3. 3Set how many terms you want listed — the nth term and running total appear instantly.

Worked example

Using the values the calculator loads with:

Inputs

  • First term a₁2
  • Multiplier r1.5
  • Added constant d3
  • Terms to generate10

Results

  • nth term301.546875
  • First terms2, 6, 12, 21, 34.5, 54.75, 85.125, 130.688, 199.031, 301.547
  • Sum of all terms846.640625
  • Long-run limitDiverges (|r| ≥ 1)
  • BehaviourGrowing without bound

Frequently asked questions

Can it do Fibonacci?

Fibonacci needs the two previous terms, so it is a second-order recurrence. This tool covers first-order rules of the form aₙ = r·aₙ₋₁ + d.

What is the fixed point?

The value where the sequence stops changing: d ÷ (1 − r), which the sequence approaches when |r| < 1.

About this calculator

Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.