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Continued Fraction Calculator

Convert any real number into its continued fraction expansion. Specify the decimal value and the maximum number of terms for the expansion.

Result
Please check your inputs.

๐Ÿ“– How to Use This Tool

Enter the real number you want to expand (e.g., 3.14159 for ฯ€) in the 'Decimal Value' field.
Set the 'Maximum Number of Terms' to control how many terms the continued fraction will have (e.g., 10 for a moderate depth).
Click the 'Calculate' button to generate the continued fraction expansion.
Review the output, which shows the sequence of partial quotients (a0, a1, a2, ...) and the corresponding rational approximations at each step.
Use the results for further analysis, such as comparing convergents or studying the pattern of terms.

๐Ÿ“ What Is Continued Fraction Calculator?

A continued fraction is a way to represent a real number as a sequence of integers, written in the form a0 + 1/(a1 + 1/(a2 + 1/(a3 + ...))). Unlike decimal expansions, continued fractions often reveal deep mathematical patterns and give the best rational approximations to any number. For example, the continued fraction for ฯ€ starts [3; 7, 15, 1, 292, ...] and yields fractions like 22/7 and 355/113.

This tool matters because it makes exploring these representations quick and intuitive. Whether you're a student learning number theory, a researcher needing rational approximations, or a curious mind investigating irrationals like โˆš2 or e, the Continued Fraction Calculator saves time and provides clear results. It turns a manual, error-prone process into a simple input-output interaction, helping you focus on insights rather than computation.

๐Ÿงฎ Formula

Standard continued fraction: x = a0 + 1/(a1 + 1/(a2 + 1/(a3 + ...))) where a0 is the integer part of x. For i โ‰ฅ 1, set remainder r = x - a0, then a1 = floor(1/r). Repeat: new remainder = 1/r - a1, then a2 = floor(1/new remainder), and so on. The tool applies this algorithm iteratively up to the specified number of terms.

๐Ÿ’ก Tips for Best Results

โœจ๐Ÿงฎ Use the calculator to compare different irrational numbersโ€”notice how ฯ€ has a long pattern while e has a regular one.
โœจ๐Ÿ”„ Start with a small max terms (like 5) to get simple rational approximations for quick estimates in calculations.
โœจ๐Ÿ” For negative numbers, note that the integer part is taken as floor (e.g., -3.14 becomes -4 + 0.86), so the continued fraction may differ from some textbooksโ€”verify if needed.
โœจ๐ŸŽฏ Increase max terms for greater accuracy, but remember that irrationals never terminate; the more terms, the closer the approximation.

โ“ Frequently Asked Questions

What is a continued fraction used for?
They provide the best rational approximations to real numbers. For example, ฯ€ approximated by 22/7 or 355/113 comes directly from its continued fraction. They're also used in cryptography, solving Pell's equation, and analyzing Diophantine approximations.
Can I enter fractions or decimals?
Yes, you can enter any real number as a decimal (e.g., 1.41421356 for โˆš2). The calculator interprets it as a floating-point number and computes the continued fraction expansion accordingly.
Why is there a maximum terms limit?
Since infinite continued fractions exist for irrational numbers, we must stop computation somewhere. The limit prevents infinite loops and lets you control the depth of approximation, balancing accuracy with computational time.

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