83*2^1536-1
 

k=83 is also prime for 1536.

Harvey563 :redface:

[QUOTE=Harvey563]k=83 is complete to 200000, & prime for 2, 4, 8, 10, 14, 18, 22, 24, 26, 28, 36, 42, 58, 64, 78, 158, 198, 206, 424, 550, 676, 904, 1276, 1374, 1642, 2124, 2796, 5266, 5318, 8828, 11638, 22968, 35836,53348, 55808, 79826, 105282, 112418, 129804, 144456.

I'm reserving k=33 to 200000.

Harvey563[/QUOTE]


I have a box at home working on 33.
When I get home tonight I'll update the stats and tell where to start.
I was near 56k this morning.

Joss

Hi Harvey563,

The stats for 33 is now updated.
You should start near 82k

keep on priming.

Joss

k=87, complete to 200000
 

I checked k=87 from 20000 to 200000 and found the following prime values: 21758, 23554, 24582, 27526, 28581, 29306, 29588, 36101, 36681, 41378, 45689, 55769, 56049, 65676, 77361, 96426, 110189, 128630, 142738, 154352, 155794, 188689.

I'm reserving k=91 to 200000.

k=33 is currently at 111000, k=21 at 495000, k=27 at 409000, & k=31 at 426000.

Harvey563
:cool:

k=21 complete to 500000
 

I have completely checked k=21 to 500000, last prime found 348547. I stopping here, so k=21 is up for grabs.

Harvey563
:yawn:

k=171 complete to n=200000
 

Hi all,

Here are the results for k=171.

k=171: n=2, 3, 5, 10, 25, 29, 39, 73, 103, 109, 123, 198, 378, 434, 825, 925, 1265, 1802, 2134, 2199, 2629, 3154, 3490, 4093, 4814, 5490, 7029, 9074, 9298, 10249, 10505, 12185, 16382, 19030, 26237, 28890, 40123, 61483, 129309, 133527, 182745

Best regards,
masser

k=91, complete to 200000
 

I have checked k=91 from 40000 to 200000 & found the following primes: 45373, 53441, 77013, 86329, 89853, 90341, 104783, 169779, 187407.

I'm reserving k=93 to 200000.

Harvey563

k=39 and k=41 complete to n=500000
 

k=39 and k=41 have been completed to n=500000, where I'm stopping.

The next two k I'm taking are: k=95 and k=99

-- Thomas11 :rolleyes:

I'm going away for the weekend, so I won't be able to update the stats.

Joss

k=93 to 200000, k=115 reserved
 

I checked 93*2^n-1 from 74595 to 200000 & found the following primes: 78192, 81294, 103744, 107991, 174412, 176479.
I'm reserving k=115 to 200000.

Harvey563

k=89
 

k=89 checked to n=275000.

Found primes for n = 56968, 68632, 185868, and 208824.
56968 has been already on the Keller's list.

k=53 and k=79 also checked to n=275000. No new primes found. I'm now ksieve-ing these three k's and will continue testing them for a while.