math calculator
Fibonacci & Golden Ratio Calculator
Generate Fibonacci numbers, check sequence membership, and solve Golden Ratio proportions.
Inputs
Results
Check Number Result
Is a Fibonacci Number
Sequence Output
Gessel\'s Theorem Proof
To check if 55 belongs to the sequence, evaluate Gessel's Theorem:
Since \(\sqrt{15129} = 123\) is a perfect square, 55 is a Fibonacci number.
Golden Ratio Convergence
| Terms | Fraction | Decimal Ratio |
|---|---|---|
| F(2)/F(1) | 1 / 1 | 1.000000 |
| F(3)/F(2) | 2 / 1 | 2.000000 |
| F(4)/F(3) | 3 / 2 | 1.500000 |
| F(5)/F(4) | 5 / 3 | 1.666667 |
| F(6)/F(5) | 8 / 5 | 1.600000 |
| F(7)/F(6) | 13 / 8 | 1.625000 |
| F(8)/F(7) | 21 / 13 | 1.615385 |
| F(9)/F(8) | 34 / 21 | 1.619048 |
| F(10)/F(9) | 55 / 34 | 1.617647 |
| F(11)/F(10) | 89 / 55 | 1.618182 |
Formula
Fibonacci and Golden Ratio Formulas
F(n) = F(n-1) + F(n-2), \quad \phi = \frac{A+B}{A} = \frac{A}{B} \approx 1.618034The Fibonacci sequence generates numbers by adding the two previous terms. The Golden Ratio represents the proportion of division that satisfies aesthetic symmetry.
Step by step
How the calculation works
- 1Use the Fibonacci tab to generate terms, verify sequence membership, and analyze convergence ratios.
- 2Use the Golden Ratio tab to divide layout elements or scales using the mathematical constant 1.618034.
- 3Study the step-by-step proofs and view the interactive Golden Rectangle spiral diagram.
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