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A120497
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Positive integers whose number of divisors is a perfect power.
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0
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1, 6, 8, 10, 14, 15, 21, 22, 24, 26, 27, 30, 33, 34, 35, 36, 38, 39, 40, 42, 46, 51, 54, 55, 56, 57, 58, 62, 65, 66, 69, 70, 74, 77, 78, 82, 85, 86, 87, 88, 91, 93, 94, 95, 100, 102, 104, 105, 106, 110, 111, 114, 115, 118, 119, 120, 122, 123, 125, 128, 129, 130, 133, 134
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OFFSET
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1,2
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LINKS
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MATHEMATICA
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Join[{1}, Select[Range[150], GCD@@FactorInteger[DivisorSigma[0, #]][[All, 2]]>1&]] (* Harvey P. Dale, Oct 19 2022 *)
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PROG
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(PARI) v=[1]; for(n=2, 134, if(ispower(numdiv(n)), v=concat(v, n))); v \\ Nick Hobson, Nov 29 2006
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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EXTENSIONS
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More terms from Nick Hobson, Nov 29 2006
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STATUS
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approved
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