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Search: id:A138051
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| A138051 |
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Numbers n such that 27^n + 2 is prime. |
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+0
6
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| 0, 1, 5, 8, 12, 21, 41, 42, 81, 105, 121, 377, 501, 2401
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OFFSET
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1,3
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COMMENT
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All terms are the exact thirds of terms of A051783 that are divisible by 3.
One further term (14597) was found by Henri Lifchitz in 2004 - see the PRP Records link.
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LINKS
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Henri & Renaud Lifchitz, PRP Records.
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MATHEMATICA
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Do[ f = 27^n + 2; If[ PrimeQ[ f ], Print[ {n, f} ] ], {n, 1, 2500} ]
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CROSSREFS
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Cf. A051783 = Numbers n such that 3^n + 2 is prime. Cf. A087885 = Numbers n such that 5^n + 2 is prime. Cf. A090649, A109076, A113480, A138048, A138049, A138050, A087886, A113481.
Sequence in context: A134208 A115072 A114644 this_sequence A026279 A124434 A164128
Adjacent sequences: A138048 A138049 A138050 this_sequence A138052 A138053 A138054
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KEYWORD
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hard,more,nonn
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AUTHOR
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Alexander Adamchuk (alex(AT)kolmogorov.com), Mar 02 2008
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