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A096498
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Prime before n-th repunit.
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18
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7, 109, 1109, 11093, 111109, 1111091, 11111101, 111111109, 1111111097, 11111111059, 111111111103, 1111111111093, 11111111111053, 111111111111053, 1111111111111039, 11111111111111107, 111111111111111091, 1111111111111111037, 11111111111111111027, 111111111111111111053, 1111111111111111111097
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OFFSET
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2,1
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LINKS
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FORMULA
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MAPLE
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seq(prevprime((10^n-1)/9), n=2..50); # Robert Israel, Nov 13 2017
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MATHEMATICA
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Table[NextPrime[(10^n - 1)/9, -1], {n, 2, 22}] (* updated by Michael De Vlieger, May 02 2016 *)
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PROG
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(PARI) a(n) = precprime((10^n-1)/9 - 1); \\ Michel Marcus, May 02 2016
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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