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A057203
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Numbers k such that 2^k + 23 is prime.
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18
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3, 7, 39, 79, 359, 451, 1031, 1039, 11311, 30227, 47599, 55731, 307099, 351831, 418851
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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For k = 39, 2^39 + 23 = 549755813911 is prime.
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MATHEMATICA
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Do[ If[ PrimeQ[2^n + 23], Print[ n ]], {n, 1, 5000} ]
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PROG
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CROSSREFS
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Cf. A019434 (primes 2^k+1), A057732 (2^k+3), A059242 (2^k+5), A057195 (2^k+7), A057196(2^k+9), A102633 (2^k+11), A102634 (2^k+13), A057197 (2^k+15), A057200 (2^k+17), A057221 (2^k+19), A057201 (2^k+21), this sequence (2^k+23).
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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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