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Old 2005-12-12, 13:21   #1
devarajkandadai
 
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Default A counterexample-anyone-II

I have a hunch that the factors of a Carmichael Number cannot all be
Mersenne.Counterexamples are welcome.
A.K. Devaraj
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Old 2005-12-12, 15:08   #2
alpertron
 
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The prime factors of 1105 (the second Carmichael number) are 5, 11 and 17.

None of these prime factors are Mersenne numbers.

Last fiddled with by alpertron on 2005-12-12 at 15:10 Reason: Fix typo
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Old 2005-12-12, 15:22   #3
alpertron
 
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If you want that all prime factors of the Carmichael number have to be Mersenne numbers, it cannot be of the known form (6k+1)(12k+1)(18k+1), where each factor is prime. But most Carmichael numbers do not have this form.
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Old 2005-12-12, 16:04   #4
Citrix
 
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All mersenne are base 2 prime? So all Mp are counter examples
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