Fibonacci numbers
Fibonacci numbers: use index n (f₀ = 0, f₁ = 1). Review the formula, worked example and calculation steps.
Inputs
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Formula & explanation
Fₙ = Fₙ₋₁ + Fₙ₋₂
Variables & units
- Index n (F₀ = 0, F₁ = 1)
- Numeric value · minimum 0, maximum 500
Worked example
F₁₀ = 55.
Assumptions
Uses zero-based indexing and exact integer arithmetic.
Formula version 1.0.0. JavaScript floating-point arithmetic applies. Results display up to 6 decimal places; stored values retain available precision. Use the units shown.
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