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Mathematicians hunting prime numbers discover infinite new pattern

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Re: Mathematicians hunting prime numbers discover infinite new pattern

#61
post #48

Earlier quoted context omitted.

If I handed you 1 apple, and then handed you another apple, you wouldn't be surprised to find that you had 2 apples. The same trick works with oranges and pears.

Zero, one, infinity.

Infinity, aka 2 or more. I agree that those are truly three distinct classes of quantity/identity

Re: Mathematicians hunting prime numbers discover infinite new pattern

#63

I hope the twin prime conjecture will become a theorem during the remainder of my lifetime that's why I already got the double twin prime conjecture ready: there exists an infinite number of consecutive twin primes. 3 examples: 11,13; 17,19. 101,103;107,109, AND 191,193;197,199... I know of another example near the 800s there's also the dubious, or trivial, or dunno (gotta generalize this pattern as well) of the firs…

BTW the phone number in Jenny's song, 867-5309, is a twin prime (867-5311).

Re: Mathematicians hunting prime numbers discover infinite new pattern

#64
post #7

I'm a little confused at the significance here. Before I read the definition of the M_a, this seemed crazy, but on actually reading it, M_1 is just the sum-of-divisors function (usually denoted sigma). So, n is prime iff M_1(n)=n+1. That's much simpler than the first equation listed there! Indeed, looking things up, it seems that in general the functions M_a can be written as a linear combination (note: with polynomi…

I agree that the observation "M_1(n) = n+1 iff n is prime" is elementary. It certainly motivates some intuition behind the investigation in this paper, but I'd loathe to call it obvious.

Note that the paper studies equations with polynomial coefficients on McMahon series. That is, the n+1 in our trivial observation is "stray" in a sense.

For an at-a-glance indication of nontriviality, look no further than the conjecture associated with Theorem 1.2 -- that there are exactly five equations of this sort which are prime indicators. That seems spooky, to me; I can't help but wonder what structure underlies such a small number of relations.

Re: Mathematicians hunting prime numbers discover infinite new pattern

#65
post #7

I'm a little confused at the significance here. Before I read the definition of the M_a, this seemed crazy, but on actually reading it, M_1 is just the sum-of-divisors function (usually denoted sigma). So, n is prime iff M_1(n)=n+1. That's much simpler than the first equation listed there! Indeed, looking things up, it seems that in general the functions M_a can be written as a linear combination (note: with polynomi…

The M functions are the MacMahon’s partition functions (see the paper [1]). They were not known to relate to the sum of divisors. The M_a function counts partitions in a parts but weighing multiplicities in the partion. [1]: https://arxiv.org/abs/2405.06451

M_1 is obviously just sigma. That's straight from the definition, you can't tell me that wasn't known.

As for the higher ones, I'm having trouble finding a proper citation saying that this was known earlier, but this math.stackexchange answer asserts that MacMahon himself worked some of this out: https://math.stackexchange.com/a/4922496/2884 No proper citation though, annoying.

When you say "this wasn't known", on what basis is that? It's very hard to be sure that something wasn't known unless you're an expert on that particular thing!

Re: Mathematicians hunting prime numbers discover infinite new pattern

#66

I hope the twin prime conjecture will become a theorem during the remainder of my lifetime that's why I already got the double twin prime conjecture ready: there exists an infinite number of consecutive twin primes. 3 examples: 11,13; 17,19. 101,103;107,109, AND 191,193;197,199... I know of another example near the 800s there's also the dubious, or trivial, or dunno (gotta generalize this pattern as well) of the firs…

The broader generalization you're headed towards is https://en.wikipedia.org/wiki/Dickson%27s_conjecture (or the even more general https://en.wikipedia.org/wiki/Schinzel%27s_hypothesis_H) which basically say that the twin prime conjecture is true for every linear/polynomial generalization of twin primes.

Re: Mathematicians hunting prime numbers discover infinite new pattern

#68
post #5

This sort of thing makes me feel there is some deep understanding of reality only inches away from us, we glimpse it through these patterns but the secret remains hidden.

Wouldn't it be fun if someone out there already knows a simple way to determine if a number is prime without factoring, but to them it is so obvious that they didn't even consider others may be interested.

Since 2002 this has been known, and it's one of the least intuitive things in modern math. (versions with probability of 1-\epsilon have existed since Miller-Rabin in 1976)

Re: Mathematicians hunting prime numbers discover infinite new pattern

#69
post #7

I'm a little confused at the significance here. Before I read the definition of the M_a, this seemed crazy, but on actually reading it, M_1 is just the sum-of-divisors function (usually denoted sigma). So, n is prime iff M_1(n)=n+1. That's much simpler than the first equation listed there! Indeed, looking things up, it seems that in general the functions M_a can be written as a linear combination (note: with polynomi…

Can you elaborate? How does this result become less surprising if you know that? Personally I would not have guessed that there are infinitely many characterisations of P involving sums-of-powers-of-divisors either.

I mean, if you can do something a simple way, it's not that surprising that you can also do it a complicated way, I'd say.

Re: Mathematicians hunting prime numbers discover infinite new pattern

#70

Earlier quoted context omitted.

I thought it was a smooth continuous manifold

To what extent are the Planck length and Planck second confirmed smallest discrete units?

I was referring to spacetime in GR is modeled as smooth continuous manifold. In case you're serious though, planck length are not some fine-grained pixels/voxels in the cartesian 3d world, at least not confirmed; in-fact planck units are derived scales.
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