Why Is Proving the Infinity of Fibonacci Primes So Challenging?

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Discussion Overview

The discussion centers around the challenge of proving whether there are infinitely many Fibonacci primes. Participants explore various mathematical approaches and conjectures related to this open problem, including the application of set theory and the properties of prime numbers within the Fibonacci sequence.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Some participants note that it is currently unknown if there are infinitely many Fibonacci primes and express curiosity about the underlying mathematical principles that make this proof challenging.
  • One participant suggests using Cantor's set theory to compare the set of Fibonacci primes with the natural numbers, arguing that both have cardinality aleph null, which could imply the infinitude of Fibonacci primes.
  • Another participant proposes a conjecture involving relationships between Fibonacci numbers and primes, suggesting a recursive structure that could lead to a proof or disproof of the infinitude of Fibonacci primes.
  • A participant references Dedekind's concept of infinite sets and questions the ease of establishing a one-to-one correspondence between Fibonacci primes and natural numbers, emphasizing that proving such a correspondence is critical to demonstrating the infinitude of Fibonacci primes.
  • There is a discussion about the nature of the terms generated in the proposed conjectures, with some participants questioning whether new terms in the sequences are necessarily prime or could have prime factors that are new primes.
  • One participant clarifies their conjecture, distinguishing between the Fibonacci series and the series generated by their proposed relationships, and emphasizes the importance of odd-indexed Fibonacci numbers being prime for indices greater than 4.

Areas of Agreement / Disagreement

Participants express a range of views on the methods to approach the problem, with no consensus on a definitive proof or disproof of the infinitude of Fibonacci primes. The discussion remains unresolved, with competing ideas and conjectures presented.

Contextual Notes

Participants highlight the complexity of establishing a one-to-one correspondence and the assumptions involved in their conjectures. There are unresolved mathematical steps and dependencies on definitions related to the properties of Fibonacci numbers and primes.

fibonacci235
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I have read that we do not know if there are an infinite number of Fibonacci primes. So far, no one has produced a proof to show if they are infinite. I wanted to know why this seems to be so challenging? I'm sure it is, and maybe there is a subtle mathematical principle I am missing.

I thought of using Cantor's set theory. I essentially would compare the set of Fibonacci primes with the natural numbers and since both have cardinality aleph null, that should imply that the Fibonacci primes are infinite. Right?

If anyone has any insight into this open problem, please let me know. I would be very interested in your input.
 
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I essentially would compare the set of Fibonacci primes with the natural numbers and since both have cardinality aleph null,

That is exactly what one would like to prove isn't it? But how do we?
 
pessimist said:
That is exactly what one would like to prove isn't it? But how do we?
Maybe a step to prove or disprove might be to prove my conjecture: Fib(2n) = A(n)*Fib(n);A(3n) = B(n)*C(n); C(5n) = D(n)*C(n);D(7n)=E(n)*D(n);E(11n)=F(n)*E(n)... This continues undefinitly and with each increase in an alpha the constant numerical multiplyer in the index is the next prime in the sequence of primes. All values set forth are integers.
 
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Dedekind proposed that an infinite set can be set up with a one-to-one correspondence with a proper subset of itself. I think it would be easy to create a one-to-one correspondence between the natural numbers and every Fibonacci prime because Fibonacci primes are subsets of the natural numbers. Also all Fibonacci primes are unique and so are all the natural numbers. This correspondence would simply go on ad infinitum.

The fact the no one has come forward with a proof makes me wonder how naive my method of attack is.
 
fibonacci235 said:
Dedekind proposed that an infinite set can be set up with a one-to-one correspondence with a proper subset of itself. I think it would be easy to create a one-to-one correspondence between the natural numbers and every Fibonacci prime because Fibonacci primes are subsets of the natural numbers. Also all Fibonacci primes are unique and so are all the natural numbers. This correspondence would simply go on ad infinitum.

The fact the no one has come forward with a proof makes me wonder how naive my method of attack is.


Dedekind did indeed prove that an infinite set can be set up in a bijection with a proper subset of itself. But that just proves the existence of A proper subset (say in N) to which it is bijective (say even natural numbers). It doesn't mean that "Given any proper subset of an infinite set, there exists a bijection between them."


For example,
1. N is a proper subset of R, but there is no bijection. (or one to one correspondence from R to N for that matter)
2. {1,2,3,4} is a proper subset of N, does that mean there exists a bijection?

You seem to suggest that showing that a one one correspondence exists is a very easy job, I would like to highlight that that would be the end of the proof that there are infinitely many Fibonacci primes.
 
pessimist said:
That is exactly what one would like to prove isn't it? But how do we?

In case this wasn't clear I meant we have to prove that cardinality of the set of Fibonacci primes is aleph null.

ramsey2879 said:
Maybe a step to prove or disprove might be to prove my conjecture: Fib(2n) = A(n)*Fib(n);A(3n) = B(n)*C(n); C(5n) = D(n)*C(n);D(7n)=E(n)*D(n);E(11n)=F(n)*E(n)... This continues undefinitly and with each increase in an alpha the constant numerical multiplyer in the index is the next prime in the sequence of primes. All values set forth are integers.


How do you say that each new term is a next prime? It could be that it has a prime factor that is a new prime but may not be prime itself?
 
pessimist said:
In case this wasn't clear I meant we have to prove that cardinality of the set of Fibonacci primes is aleph null.




How do you say that each new term is a next prime? It could be that it has a prime factor that is a new prime but may not be prime itself?
I did not say that each new term is a next prime, I said that the index multiplyer is a next prime. That is I identified the Fibonacci series by Fib which is distinct from the A,B,C,D,E and F series. You determine the A series by dividing Fib(2n) by Fib(n) to get A(n). Then you divide A(3n) by A(n) to get B(n) etc. My last relation was that E(11n) = E(n)*F(n) for all n. So after determining the F series, you would use the relation F(13n) = F(n) * G(n) (i.e., F(13) = F(1)*G(1), F(26) = (F2)*G(2), F(39)=F(3)*G(3)...). Then after determining the G series by dividing F(13), F(26), F(39) ... respectively by F(1), F(2), F(3) ... , you would use the relation G(17n) = G(n)*H(n) to determine the H series (if your computer was powerful enough). I know it is a stretch to go from this conjecture to topic of the post but both involve a relationship between primes and the Fibonacci series, so there could be a connection. One thing is certain, only Fibonacci numbers with a odd index can be prime if the index is greater than 4.
 

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