[QUOTE=Thomas11;535508]283*2^68047311 (2048431 digits) :smile:[/QUOTE]
Great Start of the Year! Last year (2019) we had to wait 60 days more to get a prime over 2 million digits. 
[QUOTE=Thomas11;535508]283*2^68047311 (2048431 digits) :smile:[/QUOTE]
Congratulations! 
1901*2^1958701 is prime! (58967 decimal digits)
It is not much but it is a start, once I determined how to use [I]NewPGen[/I]. 
[QUOTE=storm5510;536431]1901*2^1958701 is prime! (58967 decimal digits)
It is not much but it is a start, once I determined how to use [I]NewPGen[/I].[/QUOTE] You should use the "post small primes... here" thread for primes smaller than the top5000 list cutoff, presently in the vicinity of 2^1.4M. Also, newpgen is very very slow for this form of prime. The srsieve family of programs is an order of magnitude or so faster; srsieve to create the sieve initially, then sr1sieve to sieve a single "k" of k*2^n1. If you're interested in multiple k's, sr2sieve is your hero. sr1sieve speaks the same format as newpgen, so you can also use newpgen to create a sieve file, and then use sr1sieve to find factors. I forget if it's 10x or 20x faster, but it's really really fast. Command line, though all the good stuff is, around here. Have a look at [url]https://www.rieselprime.de/default.htm[/url] to see what primes are known for individual k's. For 1901, that's 2, 62, 66, 210, 290, 602, 726, 938, 998, 21342, 195870, 239030, 335018. 
[QUOTE=VBCurtis;536450]You should use the "post small primes... here" thread for primes smaller than the top5000 list cutoff, presently in the vicinity of 2^1.4M...[/QUOTE]
Done. There has been no activity on that thread since 2017, until now. [QUOTE=VBCurtis;536450]The srsieve family of programs is an order of magnitude or so faster; srsieve to create the sieve initially, then sr1sieve to sieve a single "k" of k*2^n1. If you're interested in multiple k's, sr2sieve is your hero. sr1sieve speaks the same format as newpgen, so you can also use newpgen to create a sieve file, and then use sr1sieve to find factors. I forget if it's 10x or 20x faster, but it's really really fast. Command line, though all the good stuff is, around here. [/QUOTE] I would like to take a look at these. I will look around for them. 
[URL="https://primes.utm.edu/primes/page.php?id=130384"]69*2^66399711[/URL] is prime! (1998833 decimal digits) Time : 2777.921 sec.
This prime has taken many years for Vincent and me to find, but, oh boy, is it worth it! :beer: :party: 
[QUOTE=paulunderwood;536842][URL="https://primes.utm.edu/primes/page.php?id=130384"]69*2^66399711[/URL] is prime! (1998833 decimal digits) Time : 2777.921 sec.
This prime has taken many years for Vincent and me to find, but, oh boy, is it worth it! :beer: :party:[/QUOTE] 3x HURRAY!!! 
Congrats to both, well deserved.

Congratulations! :banana::banana::banana:
So close to 2 million decimal digits... 
If there is 1+ closeby we'll have it soon as well.
69 seems very unpredictable now because of the huge gap, yet odds are they group a little together. 
[QUOTE=diep;536869]If there is 1+ closeby we'll have it soon as well.
69 seems very unpredictable now because of the huge gap, yet odds are they group a little together.[/QUOTE] What was last prime in that sequence? 
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