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A103000
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Numbers n such that 4*10^n + 8*R_n + 1 is prime, where R_n = 11...1 is the repunit (A002275) of length n.
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2
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0, 3, 4, 6, 10, 12, 18, 40, 48, 96, 106, 114, 144, 364, 618, 1090, 11370, 59454, 196684
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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 (44*10^n+1)/9 is prime.
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LINKS
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FORMULA
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MATHEMATICA
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Do[ If[ PrimeQ[(44*10^n + 1)/9], Print[n]], {n, 0, 10000}]
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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(16)-a(18) from Kamada data by Robert Price, Dec 10 2010
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STATUS
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approved
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