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A230722
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Carmichael numbers of the form (6*k + 1)*(24*k + 1)*(30*k + 1).
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3
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126217, 68154001, 1828377001, 3713287801, 27388362001, 32071969801, 63593140801, 113267783377, 122666876401, 193403531401, 227959335001, 246682590001, 910355497801, 1389020532001, 4790779641001, 5367929037001, 6486222838801, 24572944746001
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OFFSET
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1,1
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COMMENTS
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These numbers:
- are pseudoprimes to bases 2, 3 and 5;
- do not occur in A097130 (Carmichael numbers that are not == 1 mod 24).
The number (6*k + 1)*(24*k + 1)*(30*k + 1) is in the sequence if:
- k is congruent to 5 mod 10;
- its three factors are all prime.
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LINKS
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PROG
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(Magma) [a : k in [1..1785 by 2] | IsOne(a mod CarmichaelLambda(a)) where a is (6*k+1)*(24*k+1)*(30*k+1)]
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CROSSREFS
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KEYWORD
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nonn,changed
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AUTHOR
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STATUS
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approved
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