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A220262
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Number of even semiprimes < 10^n. Number of terms of A100484 < 10^n.
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3
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0, 3, 15, 95, 669, 5133, 41538, 348513, 3001134, 26355867, 234954223, 2119654578, 19308136142, 177291661649, 1638923764567, 15237833654620, 142377417196364, 1336094767763971, 12585956566571620, 118959989688273472, 1127779923790184543, 10720710117789005897
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OFFSET
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0,2
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COMMENTS
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All such semiprimes have the form 2*p, where p is prime. - T. D. Noe, Dec 09 2012
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LINKS
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FORMULA
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MATHEMATICA
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Table[PrimePi[10^n/2], {n, 0, 14}]
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PROG
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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