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Search: id:A103092
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| A103092 |
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Numbers n such that 9*10^n-7 is prime. |
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+0
2
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| 1, 6, 9, 10, 12, 13, 23, 61, 194, 233, 549, 765, 973, 1061, 1186, 1853, 3713, 6789, 7254, 7765, 9025, 10855
(list; graph; listen)
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OFFSET
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1,2
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COMMENT
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Also numbers n such that 8*10^n + 9*R_n - 6 is prime, where R_n = 11...1 is the repunit (A002275) of length n.
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LINKS
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Makoto Kamada, Factorizations of 899...993.
Index entries for primes involving repunits.
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MATHEMATICA
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Do[ If[ PrimeQ[9*10^n - 7], Print[n]], {n, 0, 10000}]
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CROSSREFS
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Sequence in context: A070598 A124257 A066385 this_sequence A104523 A091886 A111774
Adjacent sequences: A103089 A103090 A103091 this_sequence A103093 A103094 A103095
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KEYWORD
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more,nonn
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AUTHOR
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Robert G. Wilson v (rgwv(AT)rgwv.com), Jan 19 2005
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EXTENSIONS
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One more term from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 01 2008
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