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A091121
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Number of primes of the form 7k+2 less than 10^n.
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5
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1, 4, 27, 203, 1584, 13065, 110771, 960114, 8474796, 75841428, 686342043, 6267979692, 57677527046, 534156912056
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OFFSET
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1,2
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COMMENTS
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LINKS
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MATHEMATICA
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p = Select[Table[7 i + 2, {i, 0, 10^7}], PrimeQ[#] &]; Table[Count[p, x_ /; x < 10^n], {n, 7}] (* Robert Price, May 28 2019 *)
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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