20220111, 09:53  #298 
Aug 2020
79*6581e4;3*2539e3
3·7·23 Posts 
New factorial prime
A new factorial prime was recently reported (not yet validated):
288465! + 1 It is very close to the PRPnet search wavefront, is that a coincidence? 
20220118, 23:36  #299 
Sep 2002
Database er0rr
7614_{8} Posts 
Congrats to PrimeGrid for the "321" prime 3*2^18196595  1 (5,477,722 decimal digits, rank 20)

20220120, 16:54  #300 
Sep 2002
Database er0rr
111110001100_{2} Posts 
Sniped again! Congrats to Ryan Propper for the factorial prime 308084! + 1 (1,557,176 decimal digits)

20220120, 17:54  #301 
Aug 2020
79*6581e4;3*2539e3
3×7×23 Posts 
Great to see such progress on the Factorials. Apparently there were so few over the years because few people were working on them. I still think it'd be nice if the work was organized so ranges aren't done twice or thrice, which might well be the case now.

20220120, 20:33  #302 
Jun 2012
Boulder, CO
347 Posts 
Don't know who else out there is working on these, but I've sieved (and plan to test) n! ± 1 for 300,000 <= n <= 500,000.

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