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Old 2020-02-02, 04:34   #1
devarajkandadai
 
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May 2004

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Default Algorithm for generating Carmichael numbers of type 1105

1) Let n be = = 1 (mod 3)
2)check whether n satisfying above is such that (4n+1), (12n+1) and (16n+1) are primes.
If so N = (4n+1)(12n+1)(16n+1) is a Carmichael number of type 1105.
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Old 2020-02-02, 05:54   #2
CRGreathouse
 
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Perhaps it would be easier to say:
Check whether 12n + 5, 36n + 13, and 48n + 17 are prime for some nonnegative integer n. If so, their product is a Carmichael number "of type 1105".
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Old 2020-02-02, 06:12   #3
CRGreathouse
 
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It's not particularly hard to find these; e.g., 478482994075098699894289 is the 10,000-th such Carmichael number.
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