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A102964
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Numbers n such that 3*10^n-7 is prime.
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2
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1, 2, 5, 10, 29, 39, 114, 484, 865, 4180, 5385, 13122, 13832, 22676, 25020, 30057, 35910, 37935, 42295, 50194, 110076, 184124, 191152
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OFFSET
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1,2
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COMMENTS
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Also numbers n such that 2*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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FORMULA
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EXAMPLE
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For n=1,2,5 the corresponding primes are 23,293,29993.
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MATHEMATICA
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Do[ If[ PrimeQ[3*10^n-7], Print[n]], {n, 0, 10000}]
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PROG
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CROSSREFS
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KEYWORD
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more,nonn
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AUTHOR
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EXTENSIONS
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Addition of a(12)-a(15) from Kamada data by Robert Price, Dec 12 2010
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STATUS
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approved
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