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A058037
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Numbers k such that 3^k - k is prime.
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5
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1, 2, 8, 20, 40, 104, 110, 208, 472, 832, 1982, 25628, 235532
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OFFSET
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1,2
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COMMENTS
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Except for the first term all terms are of the form 6m+2 or 6m+4. There are no further terms up to 34500. - Farideh Firoozbakht, Jul 17 2005
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LINKS
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MATHEMATICA
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Do[ If[ PrimeQ[ 3^n - n ], Print[ n ] ], {n, 0, 3000} ]
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PROG
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(PARI) for(k=1, 10^6, if(ispseudoprime(3^k-k), print1(k, ", "))); /* Joerg Arndt, Apr 07 2013 */
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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