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A225730
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Numbers k such that k < d(k)^(22/10), where d(k) is the number of divisors of k.
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3
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2, 3, 4, 6, 8, 9, 10, 12, 14, 15, 16, 18, 20, 21, 24, 28, 30, 32, 36, 40, 42, 44, 45, 48, 50, 54, 56, 60, 64, 66, 70, 72, 78, 80, 84, 88, 90, 96, 100, 108, 112, 120, 126, 132, 140, 144, 150, 156, 160, 168, 180, 192, 198, 200, 204, 210, 216, 220, 224, 228, 234
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OFFSET
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1,1
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COMMENTS
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Alternatively, we could write k^5 < d(k)^11. The last odd number is a(23) = 45.
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LINKS
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MATHEMATICA
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t = {}; Do[If[n < DivisorSigma[0, n]^(22/10), AppendTo[t, n]], {n, 10^5}]; t
Select[Range[250], #<DivisorSigma[0, #]^(22/10)&] (* Harvey P. Dale, Apr 10 2024 *)
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PROG
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(PARI) for (k=2, 20000, if (k^5 < numdiv(k)^11, print1(k, ", "))) \\ Hugo Pfoertner, Apr 25 2023
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CROSSREFS
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KEYWORD
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nonn,fini,full
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AUTHOR
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STATUS
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approved
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