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A092871
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Number of composites < 10^n.
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2
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0, 4, 73, 830, 8769, 90406, 921500, 9335419, 94238543, 949152464, 9544947487, 95881945185, 962392087980, 9653934463159, 96795058249196, 970155429577329, 9720761658966073, 97376442842345765, 975260045712259138, 9765942332723655391, 97779180397439081158
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OFFSET
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0,2
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COMMENTS
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The number 1 is omitted from the count as it is neither prime nor composite
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LINKS
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FORMULA
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EXAMPLE
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10^3=1000. 1000-2=998. a(3)=830 because the 830 composites+168 primes must total 998.
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MATHEMATICA
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Table[10^i-PrimePi[10^i]-2, {i, 14}] (* Harvey P. Dale, Oct 01 2011 *) (* Mathematica's implementation of PrimePi does not work for 10^15 or above *)
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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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