20200713, 22:48  #210 
"Sam"
Nov 2016
5^{2}·13 Posts 
Another lucky hit:
26*3^1700041+1 may be prime, but N divides 3^((N1)/3))1, restarting with a=5 Time : 938.494 sec. 26*3^1700041+1 is prime! (811128 decimal digits) Time : 946.942 sec. 
20200801, 17:44  #211 
Jun 2015
Vallejo, CA/.
3×337 Posts 
Largest prime for 2020 (till now)
TO BE VERIFIED
Congratulations to Serge Batalov. Gaussian Mersenne. #20 on the current list. 2^{15317227} + 2^{7658614} + 1 4,610,945 digits. 
20200801, 20:16  #212 
Dec 2011
After milion nines:)
1,483 Posts 

20200802, 17:36  #213 
Jun 2015
Vallejo, CA/.
3×337 Posts 

20201030, 22:13  #214 
Sep 2002
Database er0rr
2^{3}·5·97 Posts 
Congrats to Scott Brown for the "321+" prime, 3*2^16408818+1, which was 6.5 years in the making by PrimeGrid.

20201117, 21:06  #215 
Mar 2006
Germany
5555_{8} Posts 
Seems a new prime for the Riesel Problem was found: 146561*2^112808021 found by PrimeGrid's project currently in verify status.
This is, when proven, almost 3 years after the last found for this problem. 
20201201, 17:46  #216 
Sep 2002
Database er0rr
3880_{10} Posts 
"P587124"

20201201, 19:05  #217  
"99(4^34019)99 palind"
Nov 2016
(P^81993)SZ base 36
2·1,531 Posts 
Quote:


20201201, 23:49  #218 
Mar 2006
Germany
101101101101_{2} Posts 

20201211, 23:32  #219 
Dec 2011
After milion nines:)
1,483 Posts 
New 1.43M repdigit prime will appear soon :)
It was time to find something bigger after 5 years searching in this sequence :) 
20201211, 23:43  #220 
"Serge"
Mar 2008
Phi(4,2^7658614+1)/2
2567_{16} Posts 
Good! Congratulations!

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