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Old 2013-12-11, 10:38   #1
storflyt32
 
Feb 2013

2·229 Posts
Default Number question.

I found a number in Yafu's factor.log

A prime number or possible probable prime having 11943 digits.

I may have a file containing a listing of probable primes lying around somewhere, but right now I have not checked yet.

The first ten digits of this number is 1448808560. The last two digits are 71.

Can someone please give me advice. Apparently factordb does not take this number.

Thanks!
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Old 2013-12-11, 10:55   #2
xilman
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Quote:
Originally Posted by storflyt32 View Post
I found a number in Yafu's factor.log

A prime number or possible probable prime having 11943 digits.

I may have a file containing a listing of probable primes lying around somewhere, but right now I have not checked yet.

The first ten digits of this number is 1448808560. The last two digits are 71.

Can someone please give me advice. Apparently factordb does not take this number.

Thanks!
I'm not quite sure what you want to do with this number. What sort of advice are you looking for? Why is this number interesting --- that is, why should it occur in factor.log at all?


Paul
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Old 2013-12-11, 12:29   #3
storflyt32
 
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Are prime numbers or composite numbers always supposed to be meant for your checkbook or wallet?

Dealing with numbers is supposed to be fun if you are having an interest in the subject.

Please have a look at these two numbers.

Can you tell me which one is prime and which one is composite?

BTW: What is missing here? Are you perhaps able to give me the third number as well and also tell me whether it is prime, or possibly composite?

Here are the two sample numbers:

2147879044879841121935405312504492005851635600432202158153392313617683786
0522463887697117638217099126997978593342367353152166840435274606748401488
1268040978327338610009463489049252789936442586632275820120297391128316185
4248608520434212476260796683530707287137190597814949527590660584221727134
4834446132362827582456286472043672916030677233044796642125873574091654219
3562977151566875350961770268744214325327721569767452362139080286009082050
2404405877434285969214690243230973631838275531443187885792067446251919938
1211717163017615279900352566527118678991461272648796480867539485696061894
7524678336727199001619181567987600062098969915247851892800052895173228818
4735982555712216018831354399865644658358161366332429471576179164550448113
4145423024346718804838861904678067848181566674143425721597189977071297889
7341386077435893077207536500414775193289480994817


7314670534426732521183464250402225254351385483372413682012323770522829308
3326487789407886751802464385943511636838293365540264093084229874934494025
6172328486053708106632238473110849973657674010347612617282891969301194449
2816157216480883785939538442638304173887568242186377962393139148155659435
8410017951900120535835224207050904080380888479076370711731332149150855065
1835622481333727539369660619189753146732351250817069065328801474348542603
6325845078975145611806208891970806739150912687175551629830520350459365412
0827735863777042716852877156116844580930169724911755979403866154083703843
0009200188311929792435916690687510834207674737680048770349462192262699146
0681814037833710248216269218363214431905651213898107082817476258340526721
4010666747687455418416457698967347660465598497239360241126299417912049942
7046257810330758039139195696443447696816670956273505645008326422621387027
8839975771835757301651565847907099767889472980905385467661591027120006059
4734285644695541770014175439632914985211602168264663429852217962893226882
8782203233800042741451259617138712086528722227581909403222501134672583467
8383725223166060661066507411776418141059950215194978264914981665223420249
7013136557994006785136628078627657916083070816717225665327856981917141673
3859255422155510110946206417438087357549088640350274226255739714938859029
3099835946818772284794965678737801380768372274689518468801796552381586593
4715618297757081203596579488411136002971238903342334662027690138803840983
1267305662337805408199417615988749655816999982177572379635566782395282021
10968528897

Last fiddled with by storflyt32 on 2013-12-11 at 12:29
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Old 2013-12-11, 13:45   #4
LaurV
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They are both prime, one need ~40 milliseconds to prove it. It took me longer to copy/paste them between pari's accolades (due to the fact that you used hard line separation, so I had to put them in accolades).

So what?
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Old 2013-12-11, 14:14   #5
R.D. Silverman
 
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Quote:
Originally Posted by storflyt32 View Post
Are prime numbers or composite numbers always supposed to be meant for your checkbook or wallet?

Dealing with numbers is supposed to be fun if you are having an interest in the subject.

Please have a look at these two numbers.

Can you tell me which one is prime and which one is composite?

BTW: What is missing here? Are you perhaps able to give me the third number as well and also tell me whether it is prime, or possibly composite?

Here are the two sample numbers:

2147879044879841121935405312504492005851635600432202158153392313617683786
0522463887697117638217099126997978593342367353152166840435274606748401488
1268040978327338610009463489049252789936442586632275820120297391128316185
4248608520434212476260796683530707287137190597814949527590660584221727134
4834446132362827582456286472043672916030677233044796642125873574091654219
3562977151566875350961770268744214325327721569767452362139080286009082050
2404405877434285969214690243230973631838275531443187885792067446251919938
1211717163017615279900352566527118678991461272648796480867539485696061894
7524678336727199001619181567987600062098969915247851892800052895173228818
4735982555712216018831354399865644658358161366332429471576179164550448113
4145423024346718804838861904678067848181566674143425721597189977071297889
7341386077435893077207536500414775193289480994817


7314670534426732521183464250402225254351385483372413682012323770522829308
3326487789407886751802464385943511636838293365540264093084229874934494025
6172328486053708106632238473110849973657674010347612617282891969301194449
2816157216480883785939538442638304173887568242186377962393139148155659435
8410017951900120535835224207050904080380888479076370711731332149150855065
1835622481333727539369660619189753146732351250817069065328801474348542603
6325845078975145611806208891970806739150912687175551629830520350459365412
0827735863777042716852877156116844580930169724911755979403866154083703843
0009200188311929792435916690687510834207674737680048770349462192262699146
0681814037833710248216269218363214431905651213898107082817476258340526721
4010666747687455418416457698967347660465598497239360241126299417912049942
7046257810330758039139195696443447696816670956273505645008326422621387027
8839975771835757301651565847907099767889472980905385467661591027120006059
4734285644695541770014175439632914985211602168264663429852217962893226882
8782203233800042741451259617138712086528722227581909403222501134672583467
8383725223166060661066507411776418141059950215194978264914981665223420249
7013136557994006785136628078627657916083070816717225665327856981917141673
3859255422155510110946206417438087357549088640350274226255739714938859029
3099835946818772284794965678737801380768372274689518468801796552381586593
4715618297757081203596579488411136002971238903342334662027690138803840983
1267305662337805408199417615988749655816999982177572379635566782395282021
10968528897
Is there some point to this silliness?
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Old 2013-12-11, 14:46   #6
Mini-Geek
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Quote:
Originally Posted by storflyt32 View Post
I found a number in Yafu's factor.log

A prime number or possible probable prime having 11943 digits.

I may have a file containing a listing of probable primes lying around somewhere, but right now I have not checked yet.

The first ten digits of this number is 1448808560. The last two digits are 71.

Can someone please give me advice. Apparently factordb does not take this number.

Thanks!
Are you asking how to know if this number is prime? First, run a PRP test. This will be very fast. I'm guessing this has already been done, based on how you describe it being in factor.log. If N-1 or N+1's factorization is known, you can prove it very quickly using PFGW. If the number is of some other sort of special form, an efficient test might be known. If the number is of a general form, you can prove it with ECPP using Primo. It will take a while (days or weeks, at a guess)...the record for an ECPP proof is 26643 digits, so your number should be doable, but not small enough as to be easy (e.g. minutes).

Basically, any advice about this number depends heavily on what sort of number it is. (and, y'know, what sort of advice you want, which you haven't said) What special form or properties, if any, does it have?

Last fiddled with by Mini-Geek on 2013-12-11 at 14:48
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Old 2013-12-11, 15:40   #7
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These are 46^512+1 and 1036^512+1.

Factordb has thousands of numbers of this size - what leads you to say "Apparently factordb does not take this number?"
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Old 2013-12-11, 16:04   #8
LaurV
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I think he is trying to paste them into fdb in the same way as in the post, with <enter> after every 80 characters or so (see my post above) and of course, fdb believes the "each number on a line" stuff
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Old 2013-12-11, 16:50   #9
R.D. Silverman
 
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Quote:
Originally Posted by wblipp View Post
These are 46^512+1 and 1036^512+1.

Factordb has thousands of numbers of this size - what leads you to say "Apparently factordb does not take this number?"
Prime proofs for these numbers are trivial.

BTW, this is in the wrong sub-forum.

Last fiddled with by R.D. Silverman on 2013-12-11 at 16:51 Reason: Added a sentence
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Old 2013-12-11, 17:37   #10
xilman
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Quote:
Originally Posted by storflyt32 View Post
Are prime numbers or composite numbers always supposed to be meant for your checkbook or wallet?

Dealing with numbers is supposed to be fun if you are having an interest in the subject.
You won't find much disagreement from many people here with either your rhetorical question or your statement.

However, my question was real. Why are these particular numbers interesting to you? In particular, why should anyone else be interested enough in them to take the effort to test them for you, or give you any other free assistance for that matter?
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Old 2013-12-11, 19:03   #11
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Default Yes, please

I would very much like to use these numbers for my checkbook and wallet, although, for my wallet, I would need extremely large denomination currency.
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