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A065592
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Smallest prime beginning with exactly n 9's.
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12
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2, 97, 991, 99901, 99991, 9999901, 9999991, 999999929, 9999999929, 99999999907, 999999999937, 9999999999971, 99999999999923, 999999999999947, 9999999999999917, 99999999999999919, 99999999999999997, 9999999999999999919, 99999999999999999931
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OFFSET
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0,1
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LINKS
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MATHEMATICA
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fp[n_]:=Select[Join[10*n+{1, 7}, 100*n+Range[1, 99, 2]], PrimeQ, 1]; With[{ns=Table[FromDigits[PadRight[{}, n, 9]], {n, 20}]}, Join[{2}, Flatten[fp/@ns]]] (* Harvey P. Dale, May 12 2012 *)
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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