20201120, 07:29  #12 
May 2013
Germany
2×41 Posts 
10^199c
I'd like to continue with these numbers.
It will take a while. 
20201121, 15:56  #13 
May 2013
Germany
2·41 Posts 
Largest c199, splitting as p100 * q100
After a longer search, starting in September (!), I found this factorization:
Code:
10^199  5399 = 16656894422236107849246117001467083363915297020262\ 62362095233433137957466266604897548197173600787241 * 60035200719352030115130596816375251478500171431803\ 22684010592432041391073140089147545414675783616961 it is the 199digit 2brilliant number in base 10. The attached file should help to check this assumption easily. Any line in the file has two entries, the first is c, indicating the number, the second is the smallest prime factor (of 10^199c) or the letter 'p'. 
20201127, 09:16  #14 
May 2013
Germany
2×41 Posts 
10^157  2049 is brilliant
10^157  2049 is the largest 157digit number with two 79digit prime factors.
Code:
10^157  2049 1446814727739974723827555617027876206977909532017942734175294759323847644834853 6911735005366371832787385196708060058647586415356721193781047891582488320067667 
20201202, 19:40  #15  
Nov 2016
2^{2}·3·5·47 Posts 
Quote:
MODERATOR CAUTION: Please stop posting inane "observations" like this. Like the next poster, and many other users, I am sick of them. I am sure the people running projects like this know about the lacunae in their tables. If you want to do something constructive about a missing entry, fill it in or at least do something to forward that aim. Otherwise, please hold your peace. Last fiddled with by Dr Sardonicus on 20201203 at 15:37 Reason: Yellow card 

20201203, 11:50  #16 
May 2013
Germany
52_{16} Posts 

20201221, 02:25  #17  
Jan 2012
Toronto, Canada
3·19 Posts 
Quote:
Sieving of 10^199+c continues, with no even splits found so far for c < 16000. 

20201221, 08:26  #18 
May 2013
Germany
2·41 Posts 
I'd like to take 10^201  c.

20201224, 14:36  #19 
May 2013
Germany
2×41 Posts 
10^911250741 is 3brilliant
Code:
10^91  1250741 1130907742078987214643014936029 2064984395278432435681546498733 4282092540978287980470405630787 The attached file should prove this. I omitted any line where 10^91c is prime or where the smallest prime factor (of 10^91c) is smaller than 10^6. PS: I'm still playing with 10^201c. 
20201226, 11:27  #20 
May 2013
Germany
2·41 Posts 
But it does not.
The file contains 282 lines, where the smallest primefactor has 31 digits. For these numbers the attached file shows that the remaining cofactor is a 61digit prime. Now the proof should be complete. I apologize the circumstances. 
20201230, 17:14  #21  
Oct 2018
23 Posts 
Quote:
Code:
2^3119397 = 62370919584932696459960851277070596883408884321 * 66887737222666271935456033050473264106633618731 2^311+69711 = 51666465841110031879560999958408509880659269639 * 80745791522933342211102055412622336041844745081 2^31324133 = 100788170265999753017323085706257528483989089343 * 165569021385057306060482886322484491911556750213 2^313+8505 = 118458567629160086527486150975362030803169102833 * 140871184348377129067049239080578375237738238409 2^31519015 = 216834485254286594903496585433315946327767764161 * 307836619227101788652208469732562326355490574073 2^315+42701 = 228669422455046776001485409864826671274859838381 * 291904331396343474258089280492317954768687954849 

20201230, 21:24  #22 
Jan 2012
Toronto, Canada
3×19 Posts 
I have a Python web scraper that I use to check entries of the form n + c for varying c on factordb, though even filtering out composites which do not have a prime factor below 20M still generates about 3000 new factordb entries on a 100,000 search range for c. I suppose I can do some "light ecm" to further reduce that list by a factor of 5 or so, but it still takes a few hours to run a t25 on 3000+ 95digit composites.
It would be nice if there was an easy way to find the smallest number that has been uploaded to factordb larger than a given number (as well as the largest number in factordb smaller than a given number), but I'm not sure how the numbers are stored internally in the database and doing such a query may be infeasible with the current infrastructure as there are over a billion entries in there already. 
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