Is It Reasonable to Assume a Prime Gap of at Least 10 Before Twin Primes?

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Discussion Overview

The discussion revolves around the assumptions related to the distribution of twin primes and their preceding primes, particularly focusing on the gaps between them. Participants explore the implications of the Twin Prime Conjecture and the K Prime Conjecture, questioning the likelihood of having an infinite number of twin primes that are preceded by primes with specific gaps, such as at least 10 or 8.

Discussion Character

  • Exploratory
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant questions the reasonableness of assuming that an infinite number of twin primes will have a preceding prime at least 10 lower than the first twin prime, while also considering the implications of the K Prime Conjecture.
  • Another participant expresses skepticism about the likelihood of having an infinite number of twin primes with a preceding prime within a distance of 10, suggesting that the density of primes around twin pairs may not support this assumption.
  • A participant seeks to clarify whether it is reasonable to assume that not all twin primes will be preceded by a prime that is less than 10 apart, using specific examples of known twin primes.
  • Further exploration is made into the classes of consecutive primes and their relationships, with a focus on whether certain classes defined by gaps can be infinite.
  • One participant expresses a desire to show that the class of classes with gaps greater than 8 is infinite, while acknowledging the difficulty of proving such claims.

Areas of Agreement / Disagreement

Participants express differing views on the assumptions regarding the gaps between twin primes and their preceding primes. There is no consensus on the likelihood of infinite classes of primes with specific gap conditions, and the discussion remains unresolved.

Contextual Notes

The discussion includes various assumptions about the distribution of primes and the implications of conjectures, which may not be universally accepted or proven. The mathematical reasoning involves complex relationships that are not fully resolved within the thread.

Nelphine
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If we assume that the Twin Prime Conjecture is true (and thus there are infinite number of primes that are 2 apart), how reasonable is it to assume that there will be an infinite number of Twin Primes that are preceded by a prime that is at least 10 lower than the first of the Twin Primes? (I actually only need it to be at least 8 lower, but that's not actually possible, so 10 it is.) As clarification, if the preceding prime was 1000 lower than the pair of Twin Primes, that would be fine.

What if I also assume that the K Prime Conjecture holds?

In other words, even assuming that the Twin (or K) Prime Conjecture holds, what can we assume about the distance between triples of primes (as opposed to pairs of primes)
 
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My 2 cents on you first question.

I would be very, very surprised if there were an infinite number of prime twins and almost all of them had another prime close to them (say ±10 like in your example).

By the pigeonhole principle, for one of the 10 distances you would have an infinite number of occurences, which means there are an infinite number of prime triples (n, n+D, n+D+2).
This is not unreasonable in itself, but is less likely that infinitude of prime twins.

However, the vast majority of natural numbers are not primes. They generally don't tend to cling together, so I'd expect about the same density of primes around twin pairs as everywhere else. But the conjecture that there is almost always a prime in one of the 10 preceding numbers to a pair means that the density in this area is 0.1, whereas the density in \mathbb{N} is 0.

This is contrary to the usual distribution of primes. For example, you can find distances between consequtive primes that are as big as you like.
 
No, what I'm asking is:

Assuming there are an infinite number of Twin Primes, how reasonable is it to assume that NOT all twin primes will be preceded by a twin prime that is less than 10 difference.

So if I assume that p(k) and p(k+1)=p(k)+2 are a pair of twin primes, I want p(k-1)<= p(k)-8

As a specific example, since 2782991 and 2782993 are a pair of twin primes, I want 2782989, 2782987 and 2782985 to not be prime.

Obviously for any given set of twin primes this wouldn't be a reasonable assumption, but for, say, every million pairs of twin primes, would it be reasonable to assume that at least one of them held this to be true?
 
Nelphine said:
No, what I'm asking is:

Assuming there are an infinite number of Twin Primes, how reasonable is it to assume that NOT all twin primes will be preceded by a twin prime that is less than 10 difference.

So if I assume that p(k) and p(k+1)=p(k)+2 are a pair of twin primes, I want p(k-1)<= p(k)-8

As a specific example, since 2782991 and 2782993 are a pair of twin primes, I want 2782989, 2782987 and 2782985 to not be prime.

Obviously for any given set of twin primes this wouldn't be a reasonable assumption, but for, say, every million pairs of twin primes, would it be reasonable to assume that at least one of them held this to be true?
If p(k) and p(k) +2 are twin primes > 3, I think that since p(k)-2 and p(k)-8 would both be divisible by 3, it would not be unreasonable for large p(k) to assume that on average, p(k) - 4 and p(k) -6 are also not prime.
 
Let (p,q,r) be any three consecutive prime numbers, then we form classes [a,b] defined by

(p,q,r) \in [a,b] if q-p = a and r - q = b

We neglect the classes [1,2] with elemeent (2,3,5) and [2,2] with element (3,5,7)

Now consider [4,2] with elementsw (7,11,13), (13,17,19), (37,41,43), (67,71,73), ...

an further on: (103837,103841,103843), (103963,103967,109969), (104677,104681,104683)

Can we imagine, that this class is finite??
 
RamaWolf, I wouldn`t be surprised if that class was infinite. However, that`s exactly what I don`t want. What I`m looking for is to show that the class of classes [a,2] where a > 8 is infinite.
 
Nelphine said:
RamaWolf, I wouldn`t be surprised if that class was infinite. However, that`s exactly what I don`t want. What I`m looking for is to show that the class of classes [a,2] where a > 8 is infinite.
That would be no easier to prove than to prove the Twin Prime conjecture in the first place, but it is certainly a reasonable assumption if you assume the twin prime conjecture is true.
 

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