Prime numbers from infinite prime number proof

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Discussion Overview

The discussion revolves around the exploration of prime numbers derived from the infinite prime number proof, specifically focusing on the method of generating new primes by taking the product of a finite set of primes and adding or subtracting one. Participants consider the naming conventions for these primes and the question of whether there are infinitely many of them.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant describes a method for generating primes by taking the product of all primes up to a certain point and adding or subtracting one, questioning if these primes have a special name.
  • Another participant notes that they do not know a specific name for primes of the form \pm1+\prod_{p\in P} p, where P is a finite set of primes, and expresses skepticism about the interest in the primality of such numbers.
  • A third participant identifies that the products of the first n primes are known as primorials and explains that adding or subtracting one yields the Euclid numbers and Kummer numbers, respectively, suggesting that the prime versions of these numbers could be termed "Euclid primes" or "Kummer primes," though this terminology is not widely used.
  • This participant also mentions that the question of whether there are infinitely many prime Euclid numbers remains unsolved.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the naming of the primes generated by this method, and there is uncertainty regarding the infinitude of prime Euclid numbers.

Contextual Notes

The discussion includes assumptions about the properties of prime numbers and the implications of the infinite prime proof, which are not fully resolved. The terminology used for the generated primes is not standardized, leading to ambiguity.

jfizzix
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I imagine most everyone here's familiar with the proof that there's an infinite number of primes:

If there were a largest prime
you could take the product of all prime factors
add (or take away) 1 and get another large prime (a contradiction)

So what if you search for larger primes this way?

(2,3,5,7,11,13)

(2*3) +-1 = 6 +-1 = {5,7}
(2*3*5) +-1 = 30+-1 = {29.31}
(2*3*5*7)+-1 = 210+-1 = {209,211} (209 is not prime)
(2*3*5*7*11)+-1 = 2310+-1 = {2309,2311}
(2*3*5*7*11*13)+-1 = 30030+-1={30029,30031} (30031 is not prime)

I have two questions:
Do prime numbers of this sort have a special name? (like Marsenne primes are (powers of 2) +-1?)
Are there infinitely many of them?

This was just an odd thought I had. You can keep going and find products where neither one above or one below is a prime.
 
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I don't know a name of primes of the form \pm1+\prod_{p\in P} p for P a finite set of primes.

One comment, though. I'm not sure whether primality/non-primality of numbers of the above form is that interesting ("interesting" being too subjective for my comment to make any sense :P). The argument to which you're referring generates primes like that based on a hypothesis we know to be false: namely, that P can be chosen to be the finite set of all primes.
 
The products of the first n primes are called the primorials.

If you add 1 to these, you get the Euclid numbers.

If you subtract 1 instead, you get the Kummer numbers.

The prime Euclid numbers (or prime Kummer numbers) don't have special names. They are just the "prime Euclid numbers." I guess you could call them "Euclid primes" (or "Kummer primes") if you wanted to be fancy, but this is not widely-used terminology. You can find a list of the first few prime Euclid numbers on OEIS. I believe the question of whether this list goes on forever is unsolved.

As far as I know, the combined list of prime Euclid numbers and prime Kummer numbers has no name (and isn't even on OEIS as far as I can tell).
 
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Thanks for the info:)
 

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