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Old 2017-08-20, 17:42   #56
firejuggler
 
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Apr 2010
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a c28 has been found
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Old 2017-09-30, 16:35   #57
chris2be8
 
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Does anyone know who is adding lots of numbers like 485^1158-1 to factordb? They are appearing with status unknown faster than factordb can PRP test them.

It would be friendlier to tell factordb about the algebraic factors when they are added.

I've re-started my script to check numbers with status unknown for algebraic factors and add any factors it finds, working from 4000 digits upwards. But that's only a stopgap.

Chris
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Old 2017-09-30, 18:55   #58
rcv
 
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Quote:
Originally Posted by swellman View Post
I'm just unsure how the ElevenSmooth project was managed. There are about fifty composite cofactors (plus one unknown) listed in Factordb that do not appear on the 11S site. I'm assuming they're all interrelated, i.e. find a factor of a smaller composite on 11S and one of the bigger terms will also benefit when the factor is reported to fdb.
As you probably know, FactorDB does not have an inherent understanding of algebraic factorizations.

About five or six years ago there were many large ElevenSmooth numbers in FactorDB (i.e., numbers of the form 2^n+1, where n divides 1663200) where there were a handful of small prime factors and a handful of megacomposite factors. I attempted to work my way through the entire ElevenSmooth factorization tree to ensure that each number of those forms was the product of known factors and primitives.

Once "normalized", if that's the correct term, then "yes", a factor of a smaller primitive should appear in FactorDB's reported factorizations of the ancestors who were part of the "normalization" process. So, when you looked at 2^3326400-1, every "large" factor (whether prime or composite) represents the ultimate factor of one of the ElevenSmooth primitives. And that should remain the case as you continue to report factors.

However, if you were to look just outside the tree whose root is 2^3326400-1, you would find numbers where the primitives were not neatly separated. (Unless somebody else has undertaken a similar effort.)
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Old 2017-09-30, 22:11   #59
jcrombie
 
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If you follow the way it's done on paper with the Cunningham project, then you significantly reduce the amount of storage required. Just store factors of primitives and recalculate on the fly when required. For 485^1158-1 we don't need to store anything, we could just refer to (485^579-1) and (485^579+1).
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Old 2017-10-01, 09:19   #60
rcv
 
Dec 2011

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Quote:
Originally Posted by chris2be8 View Post
Does anyone know who is adding lots of numbers like 485^1158-1 to factordb? They are appearing with status unknown faster than factordb can PRP test them.

It would be friendlier to tell factordb about the algebraic factors when they are added.

I've re-started my script to check numbers with status unknown for algebraic factors and add any factors it finds, working from 4000 digits upwards. But that's only a stopgap.

Chris
There are tens of thousands of these entries (perhaps hundreds of thousands) in the low range of the Unknown numbers. And most of the numbers I see are of the form a^b-1. (Although some are of the type of pattern used by our old friend, user cmd.)

The best thing we, as users, might do is to feed FDB with nice factor trees, starting with the algebraic (and occasional Aurifeuillean) *primitives*. Let's give our small factors *once* to the *primitives*, not to each of the 4000-digit numbers which might contain a smaller algebraic factor's primitive.

@Chris: I have (some) experience in teaching algebraic and Aurifeuillean factor trees to FDB. And I'm willing to help. Have you collected a list of base/exponent ranges involved?

Perhaps Markus should be contacted. Does he want the users to deal with this vandalism, or does he just want to expunge everything that came from the vandal's IP address?

Last fiddled with by rcv on 2017-10-01 at 09:25
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Old 2017-10-01, 16:02   #61
chris2be8
 
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Quote:
Originally Posted by rcv View Post
@Chris: I have (some) experience in teaching algebraic and Aurifeuillean factor trees to FDB. And I'm willing to help. Have you collected a list of base/exponent ranges involved?
I don't need help, my script is adding the algebraic factors for all the a^b-1 numbers it finds. I just need to leave it running until it's gone through the range (it may take a few months but that's not a big problem).

The worse problem is numbers added as a string of digits, not an expression. I can't do anything useful with them.

Chris
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Old 2017-10-02, 13:44   #62
rcv
 
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Quote:
Originally Posted by chris2be8 View Post
I don't need help, my script is adding the algebraic factors for all the a^b-1 numbers it finds. I just need to leave it running until it's gone through the range (it may take a few months but that's not a big problem).

The worse problem is numbers added as a string of digits, not an expression. I can't do anything useful with them.

Chris
Good luck, Chris. But I fear you will never catch up. Below is a sampling of every millionth ID. Number 900000000 was entered on February 2, 2017. Number 950000000 was entered on July 31, 2017. August and September exceed the number of entries from the previous 6 months, and a large majority of the newer entries are useless. It also appears the attacker is getting more and more bold, by adding additional classes of garbage numbers. Maybe factordb needs a "proof of work", as used in blockchains, to prevent entry of completely useless numbers at no cost to the attacker.

Code:
         id          | status | length |                       number                       
---------------------+--------+--------+----------------------------------------------------
 1100000000900000000 | P      |     25 | 2894044212560751417491563
 1100000000901000000 | FF     |     29 | 17723754780876988611193626090
 1100000000902000000 | FF     |     47 | 
 1100000000903000000 | FF     |     34 | 3703711103717039257039997037901243
 1100000000904000000 | FF     |     32 | 10119289550232258292275092014003
 1100000000905000000 |        |    999 | 10^998+22417453
 1100000000906000000 | P      |    990 | (10^999+2350097)/4675692609
 1100000000907000000 | FF     |     88 | 7587579601...33
 1100000000908000000 | FF     |     20 | 29980982030602115554
 1100000000909000000 |        |   1260 | (331^509-330^509)/266258864160225303711481
 1100000000910000000 | FF     |     86 | 7630323809...52
 1100000000911000000 |        |    981 | (10^1000+19914305)/61456116871205931585
 1100000000912000000 |        |    985 | (10^1000+21159213)/8859713393305073
 1100000000913000000 | FF     |     31 | 3384445114575424237319522118359
 1100000000914000000 |        |    996 | (10^998+22718615)/465
 1100000000915000000 | FF     |     91 | 2884806400...53
 1100000000916000000 | FF     |     72 | 9457045185...72
 1100000000917000000 | CF     |    989 | (10^1000+22752475)/618351983419
 1100000000918000000 | CF     |    996 | (10^998+22952639)/327
 1100000000919000000 | FF     |     89 | 1905597835...13
 1100000000920000000 | CF     |   1000 | 10^999+2940527
 1100000000921000000 |        |    997 | (10^998+23202343)/11
 1100000000922000000 | FF     |     24 | 738958854142100215398527
 1100000000923000000 | P      |     42 | 523733957716958045592126203718080743921067
 1100000000924000000 | P      |     19 | 3399717864477400603
 1100000000925000000 | CF     |   1000 | 10^999+3348527
 1100000000926000000 | FF     |     38 | 99067828970375937092137272115502781350
 1100000000927000000 | FF     |     39 | 457170293841184099267391620122028906997
 1100000000928000000 | FF     |     37 | 3535287024350672395176373260779520999
 1100000000929000000 | FF     |     42 | 903697840840887975256203596549395150175887
 1100000000930000000 | FF     |     34 | 2139275097021898619245674895609763
 1100000000931000000 | P      |     42 | 523733957716958045592126203718080653795603
 1100000000932000000 | P      |     67 | 5391799100...59
 1100000000933000000 | P      |     42 | 523733957716958045592126203718080618572879
 1100000000934000000 | CF     |   2103 | 147^970-2910^49
 1100000000935000000 | FF     |     19 | 1905410765229631181
 1100000000936000000 | FF     |     74 | 1003886521...03
 1100000000937000000 | FF     |    108 | 4614829803...53
 1100000000938000000 | FF     |     93 | 1809090588...99
 1100000000939000000 | CF     |   6940 | 5481049165...77
 1100000000940000000 | FF     |     36 | 347867765361036361764624535629476489
 1100000000941000000 | FF     |     30 | (21220877^5-1)/21220876
 1100000000942000000 | FF     |     67 | 1184136005...11
 1100000000943000000 | P      |     68 | 7938993865...03
 1100000000944000000 | FF     |     25 | 3239333001681515844589378
 1100000000945000000 | FF     |     60 | 6153072083...39
 1100000000946000000 | FF     |     61 | 2378811325...26
 1100000000947000000 | P      |     30 | 494389845534458673425627765851
 1100000000948000000 | FF     |     48 | (86572091^7-1)/86572090
 1100000000949000000 | FF     |     48 | (99993433^7-1)/99993432
 1100000000950000000 | FF     |     21 | 398088625655164941041
 1100000000951000000 | FF     |     19 | 3212823310200606061
 1100000000952000000 | P      |     20 | 17299984290333299741
 1100000000953000000 | FF     |    100 | (1703627^17-1)/1703626
 1100000000954000000 | FF     |    104 | (186769599624616303^7-1)/186769599624616302
 1100000000955000000 | CF     |  15445 | 383838^94+100^7722
 1100000000956000000 |        |   1147 | 
 1100000000957000000 | CF     |   4799 | 2690921178...28
 1100000000958000000 | CF     |   5412 | 6330404541...82
 1100000000959000000 | CF     |   7895 | 1933564718...80
 1100000000960000000 |        |   3729 | 3536437129...07
 1100000000961000000 | FF     |     22 | 8556778994788983608339
 1100000000962000000 | FF     |     19 | 4463101554599774841
 1100000000963000000 | FF     |     95 | 9398250800...38
 1100000000964000000 | CF     |    169 | (103319887350439^13-1)/103319887350438
 1100000000965000000 | CF     |   6630 | 7327266194...64
 1100000000966000000 | FF     |     22 | 1933770422340354397873
 1100000000967000000 | CF     |    210 | (862168281937927060181^11-1)/862168281937927060...
 1100000000968000000 |        |   2761 | 4862298686...59
 1100000000969000000 |        |   3788 | 3273698841...31
 1100000000970000000 | CF     |   8836 | 1233587200...24
 1100000000971000000 | CF     |   9507 | 1278215347...01
 1100000000972000000 | CF     |  10891 | 3559572216...01
 1100000000973000000 | CF     |  11920 | 8251495301...01
 1100000000974000000 | CF     |  13215 | 1877872342...24
 1100000000975000000 | CF     |   7401 | 8612095055...95
 1100000000976000000 | CF     |   6343 | 1515948585...63
 1100000000977000000 | CF     |   1960 | 2114756195...08
 1100000000978000000 | CF     |   6093 | 1890258695...26
 1100000000979000000 | CF     |   3956 | 2428820789...02
 1100000000980000000 | CF     |  10848 | 4326617839...49
 1100000000981000000 | CF     |   6051 | 7216992894...24
 1100000000982000000 | CF     |   5224 | 1551^1637-1637^1551
 1100000000983000000 | CF     |  11635 | 100^5817+26426426487
 1100000000984000000 |        |  15956 | 1943^4852-4852^1943
 1100000000985000000 |        |  16356 | 2153^4907-4907^2153
 1100000000986000000 | CF     |   8315 | 2368^2464-2464^2368
 1100000000987000000 | CF     |  11181 | 2600^3274-3274^2600
 1100000000988000000 |        |  14924 | 2906^4309-4309^2906
 1100000000989000000 |        |  13442 | 3260^3826-3826^3260
 1100000000990000000 | P      |     83 | ((10000^23-1)/9999-23)/219978
 1100000000991000000 |        |  17087 | 4436^4685-4685^4436
 1100000000992000000 |        |   3761 | 1898868894...81
 1100000000993000000 |        |  27469 | 10^27468*3
 1100000000994000000 | CF     |   8191 | 6215179571...64
 1100000000995000000 | FF     |    111 | (17017017088^12+1)/3365480113673
 1100000000996000000 |        |   6534 | 1154974587...91
 1100000000997000000 |        |   6582 | 1339863569...07
 1100000000998000000 | FF     |     24 | 144072423069035225829571
 1100000000999000000 |        |   4901 | (305^1995-1)/2872101568838456354081604013959981...
 1100000001001000000 |        |   8496 | 3220548385...24
 1100000001002000000 |        |   8752 | 6973988096...92
 1100000001003000000 | FF     |     28 | 4229118215022440877033360947
 1100000001004000000 | FF     |     21 | 816231112528470350493
 1100000001005000000 |        |   9579 | 7936545539...88
 1100000001006000000 |        |   5374 | 699^1889-1
 1100000001007000000 |        |  10278 | 8333207607...73
 1100000001008000000 | FF     |     24 | 786330279963156175792691
 1100000001009000000 |        |  11836 | 821^4061-1
 1100000001010000000 | FF     |     20 | 69078720103003928483
 1100000001011000000 |        |  11537 | (1606^3610-3610^1606)/8055675728911642805770595...
 1100000001012000000 | CF     |   2110 | (955^718-1)/1634318514114083719803869396933
 1100000001013000000 | FF     |     24 | 205775303202062011657823
 1100000001014000000 | FF     |     65 | 2475787911...73
 1100000001015000000 | FF     |     24 | 628321561087304197773739
 1100000001016000000 |        |  13247 | 4819443453...83

Last fiddled with by rcv on 2017-10-02 at 13:56
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Old 2017-12-26, 12:42   #63
cubaq
 
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1110112 Posts
Default retrieve HP10 last line

I'd like to retrieve last component (prime or composite) of base 10 sequence.
I know how to retrieve component using it's ID
(i.e. wget -q -b -w 5 'http://factordb.com/getnumber.php?id=1100000000733584886' -O "k49.txt")
, also I have found a way to retrieve elf file
(i.e. wget 'http://www.factordb.com/elf.php?seq=4788&type=1' -O alq_4788.elf)
, but the given example works only for Aliquot sequence. No, &type=10 if not an answer.



Knowing that there is no documentation nor help option, I am asking:
How, using wget, retrieve ID, Number, or whole of last line, of base 10 sequence for given starting Number?


cubaq
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Old 2017-12-26, 17:58   #64
EdH
 
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"Ed Hall"
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I'm not at all familiar with the home prime sequences, but the way I have found what to call in the past for other types, is to use the sequence page, ask for what I want and then study the address line in the page. As an example, to get the last line for home prime 4910, I would go to the HP10 sequence page enter 49, click on Show last element, then the Show button. This gives me an html page for the last element and the address for that page is in the address bar. I use tyhat address to d/l an html page and then harvest the ID from it. You can filter out the id using grep. See if this will get you what you want:

Example using 4910:
Code:
wget "http://www.factordb.com/sequences.php?se=10&aq=49&action=last&fr=0&to=100" -O temphp.html
cat temphp.html | grep "showid"
You should be able to just sub in another number for the 49 in the example.
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Old 2017-12-27, 17:32   #65
cubaq
 
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Quote:
Originally Posted by EdH View Post
I'm not at all familiar with the home prime sequences, but the way I have found what to call in the past for other types, is to use the sequence page, ask for what I want and then study the address line in the page. As an example, to get the last line for home prime 4910, I would go to the HP10 sequence page enter 49, click on Show last element, then the Show button. This gives me an html page for the last element and the address for that page is in the address bar. I use tyhat address to d/l an html page and then harvest the ID from it. You can filter out the id using grep. See if this will get you what you want:

Example using 4910:
Code:
wget "http://www.factordb.com/sequences.php?se=10&aq=49&action=last&fr=0&to=100" -O temphp.html
cat temphp.html | grep "showid"
You should be able to just sub in another number for the 49 in the example.




EdH,


Thank You very much, it works.


cubaq
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Old 2017-12-28, 03:21   #66
EdH
 
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Quote:
Originally Posted by cubaq View Post
EdH,


Thank You very much, it works.


cubaq
cubaq,

You're quite welcome. Glad it was what you wanted.

Ed
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