How it works
Arithmetic: constant difference. Geometric: constant ratio. Fibonacci: each term is the sum of the previous two (F₀=0, F₁=1).
aₙ=a₁+d(n−1) · aₙ=a rⁿ⁻¹ · Fₙ=Fₙ₋₁+Fₙ₋₂
When to use
Use this tool when you need to: arithmetic odds: a₁=1, d=2, n=5 → a₅=9, S₅=25. Geometric powers of 2: a₈=128. Fibonacci F₁₀=55.
How to use this tool
- Enter your values in the fields above.
- Review the formula and any mode options for your problem.
- Read the result and the step-by-step solution.
Arithmetic odds: a₁=1, d=2, n=5 → a₅=9, S₅=25. Geometric powers of 2: a₈=128. Fibonacci F₁₀=55.
Frequently asked questions
- What is the Number Sequence Calculator?
- Arithmetic: constant difference. Geometric: constant ratio. Fibonacci: each term is the sum of the previous two (F₀=0, F₁=1).
- How do I use the Number Sequence Calculator?
- Enter the required values, then calculate. The Number Sequence Calculator shows results, formulas, and step-by-step work when available. No account is required.
- What formula does the Number Sequence Calculator use?
- aₙ=a₁+d(n−1) · aₙ=a rⁿ⁻¹ · Fₙ=Fₙ₋₁+Fₙ₋₂
- Average CalculatorArithmetic and weighted mean with a visual sum÷count layout and step-by-step work.
- Mean, Median, Mode, Range CalculatorArithmetic mean, median, mode(s), and range for comma-separated data — with ordered list, frequency table, and worked steps.
- Statistics CalculatorArithmetic and geometric means, σ and s, variance, quartiles, IQR, and Σx / Σx² from a comma-separated list.
- Standard Deviation CalculatorPopulation σ and sample s with variance, mean, sum, standard error, and margin of error for the mean.
- Probability CalculatorIndependent two-event probabilities, solver, series of trials, normal range area, simple favorable/total, and Bayes.
- Permutation and Combination CalculatornPr and nCr without replacement, plus with-replacement n^r and multichoose, with factorials and steps.