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Old 2009-10-05, 18:27   #1
Siemelink
 
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Jan 2006
Hungary

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Default Base 13 prime found

Hi everyone,

one of my side projects has given me a large prime. I had noticed that there was no prime with base 13 in the top 5000. So I found one:

Primality testing 6710*13^142143-1 [N+1, Brillhart-Lehmer-Selfridge]
Running N+1 test using discriminant 11, base 1+sqrt(11)
Calling Brillhart-Lehmer-Selfridge with factored part 100.00%
6710*13^142143-1 is prime! (10738.7531s+0.0591s)

Other bases that need the same treatment:
base 7, 11 have +1 but no -1
base 13 has -1 but no +1
Base 14 has no entries.

Cheers, Willem.
--
PS what would be the most fitting subforum? I decided on CRUS because this is where i hang out.
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