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A330900
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Number of terms of A066038 that do not exceed 10^n.
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0
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0, 2, 22, 130, 1196, 11698, 107315, 961924, 8641491, 78304633, 714962670, 6572968299
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OFFSET
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0,2
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COMMENTS
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Luca & Moodley (2020) conjectured that a(n) ~ exp(gamma) * A006880(n).
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LINKS
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EXAMPLE
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There are 2 terms of A066038 not exceeding 10^1: 6 and 10. Thus a(1) = 2.
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MATHEMATICA
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b[1] = 0; b[n_] := Plus @@ FactorInteger[n][[;; , 1]]; bQ[n_] := PrimeNu[n] > 1 && PrimeQ[b[n]]; p = 1; s = 0; seq = {}; Do[If[bQ[n], s++]; If[n == p, p *= 10; AppendTo[seq, s]], {n, 1, 10^6}]; seq
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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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