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A287591
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Carmichael numbers k such that k-2 and k+2 are both primes.
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4
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656601, 25536531021, 8829751133841, 60561233400921, 79934093254401, 352609909731201, 598438077923841, 976515437206401, 2122162714918401, 2789066007968241, 3767175573114801, 7881891474971361, 10740122274670881, 11512252145095521, 16924806963384321
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OFFSET
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1,1
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COMMENTS
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Rotkiewicz conjectured that there are infinitely many Carmichael numbers k such that k-2 or k+2 are primes.
The terms were calculated using Pinch's tables of Carmichael numbers (see link below).
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LINKS
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EXAMPLE
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656601 is in the sequence since it is a Carmichael number (A002997) and both 656599 and 656603 are primes.
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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