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**Stangerzv****Member**- Registered: 2012-01-30
- Posts: 179

Hi Bobbym

It would take some times and I would let you know when it is done.

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**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,845

Hi Bobby,

bobbym wrote:

Oh boy, if only some of that were true. My cousin is being kind.

I'm sure I asked you a question once...I think...possibly...

I can't find it, though. Tried inputting a question mark in Search for posts of mine that had one of those things, but that didn't do it. Hmmm...maybe I was wrong.

"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,228

About the question mark or the question?

**In mathematics, you don't understand things. You just get used to them.Of course that result can be rigorously obtained, but who cares?Combinatorics is Algebra and Algebra is Combinatorics.**

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**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,845

About ever asking you a question (just going along with the doubt you expressed).

I thought that doing a search for my posts containing a question mark would bring up all posts where I had asked a question, and I was planning to then look through them to see if I'd ever asked you one.

"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,228

Try *?*

**In mathematics, you don't understand things. You just get used to them.Of course that result can be rigorously obtained, but who cares?Combinatorics is Algebra and Algebra is Combinatorics.**

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**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,845

I already did, and it only returned 129 pages of my posts in descending date order. The first few I checked didn't have a question mark.

Maybe I've never asked a question.

"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,228

For some reason "?" is considered something else in the search.

**In mathematics, you don't understand things. You just get used to them.Of course that result can be rigorously obtained, but who cares?Combinatorics is Algebra and Algebra is Combinatorics.**

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**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,845

I'm pretty sure the search is limited, as we discussed recently in another thread. Only whole words work, I think, and some words are excluded.

I need to get some beauty sleepzzz......

*Last edited by phrontister (2013-10-21 03:03:42)*

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,228

Hi;

Okay, see you later. It looks like I will be doing the same thing.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**Stangerzv****Member**- Registered: 2012-01-30
- Posts: 179

Anybody knows how to run the primality test using AKS? Here the AKS article http://en.wikipedia.org/wiki/AKS_primality_test#History_and_running_time (I need for dummies instruction). I have ran ProvablePrimeQ[n] on the mathematica and even after more than a month still couldn't get the answer and it crashed my computer after sometimes. I need to make sure the primes here are true (especially for the large numbers).

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,228

It has been pointed out to me that it is very, very, slow.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**Stangerzv****Member**- Registered: 2012-01-30
- Posts: 179

Dear bobbym

Thanks for the info. I think I need to upgrade my computing power to do the job.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,228

I do not think so. It is very, very, very slow. Too slow to be useful except for small numbers.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**danaj****Member**- Registered: 2014-03-03
- Posts: 15

Here is an example graph showing some times for primality proving. Single threaded on a 4.3GHz machine (more details available if you'd like). I have not seen a faster AKS implementation than the B+V version here, but they could be out there. Pari/GP's APR-CL (the isprime command) runs a bit slower than WraithX's APRCL 1.1. I have no idea how fast Mathematica is (timings from this thread make me think its BPSW is quite a bit slower than the graph here, but that is independent from its proof times). Primo is the most common program used for proving large general primes.

100 digit primes can be proved extremely fast (a few milliseconds). 1000 digits will take ~2-8 minutes. For ECPP and APR-CL the time increases at about the 4th power of the number of digits (for AKS it's the 6th power). By 20k digits, expect 3 months using all cores of a 4- or 6-core machine.

I'm not sure about the various DR-restricted numbers, but the first set of unrestricted (post 109) are fairly small. E.g. p=29 => n=932651 is 213 digits, p=31 => n=2547137 is 242 digits. They grow of course, as p=59 => n=4183583 is 469 digits.

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**Stangerzv****Member**- Registered: 2012-01-30
- Posts: 179

Thanks danaj

I think having a computer with GPU processing units (NVIDIA Tesla) would make it faster due to the fact it has thousand cores per GPU. I am still working on building one with multiple GPUs, got to wait until the GPU price going down after sometimes.

*Last edited by Stangerzv (Today 12:07:18)*

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