From k>2000:

2351*2^373486-1 (112434 digits)

From the 5th drive:

129*2^603488-1 (181671 digits)

201*2^540810-1 is prime. (162803 digits)

201 has produced 11 primes from 280k to 540k. :rolleyes:
-Curtis

After a dry march - I find my third prime for k=49:
[URL="http://primes.utm.edu/primes/page.php?id=79999"]49 * 2^691469-1[/URL] (208155 digits) :grin:

From k>2000:

2053*2^375747-1 (113115 digits)

Note that this one is database Id. (submission No.?) [URL="http://primes.utm.edu/primes/page.php?id=80000"]80000[/URL] of the Top5000 database! (Though not the 80000th prime...)

181*2^823853-1 (248007 digits)

woo-hoo!

From the 5th drive:

267*2^607688-1 (182935 digits)

20152491645*2^301278-1
20152491645*2^312808-1
20152491645*2^325708-1
20152491645*2^326143-1

904883265*2^417730-1 (125759 digits)

20152491645*2^333609-1 (100437 digits)

From the 5th drive:

279*2^616044-1 (185451 digits)