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A064182
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Sum_{k <= 10^n} number of distinct primes dividing k (A001221).
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1
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0, 11, 171, 2126, 24300, 266400, 2853708, 30130317, 315037281, 3271067968, 33787242719, 347589015681, 3564432632541, 36457601891708, 372096179850464, 3790896863469849, 38562555830676602, 391760068087338367, 3975397006170581823, 40066272402579605194
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OFFSET
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0,2
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COMMENTS
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LINKS
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FORMULA
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a(n) = Sum_{k, 1, limit}, PrimePi(10^n/k); which seems to be about 10^n/2.
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MATHEMATICA
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s = 0; k = 2; Do[ While[ k <= 10^n, s = s + PrimeNu@ k; k++ ]; Print[ s], {n, 8}]
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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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