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A089684
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Numbers k such that 2*phi(k) > k.
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5
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1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, 59, 61, 63, 65, 67, 69, 71, 73, 75, 77, 79, 81, 83, 85, 87, 89, 91, 93, 95, 97, 99, 101, 103, 107, 109, 111, 113, 115, 117, 119, 121, 123, 125, 127
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OFFSET
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1,2
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LINKS
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FORMULA
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Asymptotic to c*n with c=2.045...
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MATHEMATICA
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lst={}; Do[If[2*EulerPhi[n]>n, AppendTo[lst, n]], {n, 200}]; lst (* T. D. Noe *)
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CROSSREFS
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Cf. A036798, the missing odd numbers.
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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