Can Continued Fractions be Evaluated?

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In summary, the student asked about a continued fraction that converges to a certain number, and was told it was in Sloane's list. However, the student found the fraction they were looking for was actually wrong.
  • #1
csprof2000
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If anybody can evaluate this, please let me know...

Infix notation:
1/(2+3/(4+5/(6+7/(8+9/(10+11/(...))))))

Postfix notation:
1 2 3 4 5 6 ... n ... / + / + / + / + ... / + ...
 
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  • #2
I can't evaluate it but I can look it up. It's BesselI(0,2)/BesselI(1,2). The inverse of Sloane A052119. http://www.research.att.com/~njas/sequences/A052119
 
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  • #3
Dick said:
I can't evaluate it but I can look it up. It's BesselI(0,2)/BesselI(1,2). The inverse of Sloane A052119. http://www.research.att.com/~njas/sequences/A052119

Ooops. I was reading it as a simple continued fraction, and it's not, sorry.
 
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  • #4
Why was this moved to homework help? This is no homework problem. I challenge whoever dared move this to this forum to provide the answer or relinquish their moderation powers. Silly mods.
 
  • #5
The mods are just trying to make this a livable place. Sometimes they make mistakes. A moderator that makes occasional mistakes in relocating threads is a lot better than no moderation. Trust me. But anyway, do you have a good reason for thinking there is an evaluation and why do you want to know? Just curious.
 
  • #6
If you like, one of those "silly mods" could just delete this for you.
 
  • #7
Whoa guys, no offense meant. Sheesh, serious mods.

Anywho, the reason I was wondering about this was that a student asked about it in my class. Apparently this thing does converge to around ~0.38, and I was just wondering if a more "pure" mathematician could help me out.
 
  • #8
If you think about it, it would be just as hard to 'evaluate' (express in terms of elementary functions) an arbitrary continued fraction as an arbitrary string of digits. About all you can do is see if somebody has stumbled across it somehow. I took 1+1/(2+1/(3+1/(4+1/(5+1/... and evaluated it to a reasonable number of significant digits and hunted for it in Sloane's list. Was pretty happy to find something until I realized I'd gotten your fraction wrong. I don't find a hit for your form.
 

1. What is a "Nasty Continued Fraction"?

A "Nasty Continued Fraction" is a type of mathematical expression that involves a never-ending sequence of fractions. It is typically denoted by the symbol [a0; a1, a2, a3, ...], where the a's are coefficients or constants. This type of fraction is considered "nasty" because it can be difficult to simplify or calculate.

2. How is a "Nasty Continued Fraction" different from a regular continued fraction?

The main difference between a "Nasty Continued Fraction" and a regular continued fraction is that a "Nasty Continued Fraction" has coefficients that are not necessarily integers. This makes it more complex and challenging to work with, as it requires more advanced mathematical techniques to manipulate and solve.

3. What are some real-life applications of "Nasty Continued Fractions"?

"Nasty Continued Fractions" have many applications in fields such as finance, physics, and computer science. They are used to approximate irrational numbers, model physical systems, and improve the efficiency of algorithms. For example, the Golden Ratio, which is often found in nature and used in art and design, can be expressed as a "Nasty Continued Fraction".

4. How can one simplify or evaluate a "Nasty Continued Fraction"?

There are various methods for simplifying or evaluating a "Nasty Continued Fraction". One approach is to use continued fraction arithmetic, which involves manipulating the fractions in a specific way to get a more manageable expression. Another method is to convert the "Nasty Continued Fraction" into a regular continued fraction, which may be easier to work with. Additionally, there are computer algorithms that can approximate the value of a "Nasty Continued Fraction" to a desired degree of accuracy.

5. Are there any famous examples of "Nasty Continued Fractions"?

Yes, there are several well-known "Nasty Continued Fractions" that have been studied extensively by mathematicians. One example is the continued fraction for Euler's number, e = [2; 1, 2, 1, 1, 4, 1, 1, 6, 1, 1, 8, ...]. Another famous example is the continued fraction for the square root of 2, √2 = [1; 2, 2, 2, 2, ...]. These fractions have interesting properties and have been used in many mathematical proofs and applications.

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