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Old 2006-11-24, 21:03   #1
Citrix
 
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Jun 2003

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Default Cullen prime problem (How everything began)

On http://primes.utm.edu/top20/page.php?id=6
There is an open problem to find a cullen prime p*2^p+1 where p is also prime. Has anyone done anywork on this?

I tried to write a crude sieving program. There are ~9000 candidates left under p=5 million when the range is sieved to 350 Million.

Factors available on request.

Is anyone interested in improving on these results. Writing a faster sieve software? Any thoughts on how to solve this problem?

Thanks!

Last fiddled with by hhh on 2007-03-24 at 23:21
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