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A120497 Positive integers whose number of divisors is a perfect power. 0
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 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
MATHEMATICA
Join[{1}, Select[Range[150], GCD@@FactorInteger[DivisorSigma[0, #]][[All, 2]]>1&]] (* Harvey P. Dale, Oct 19 2022 *)
PROG
(PARI) v=[1]; for(n=2, 134, if(ispower(numdiv(n)), v=concat(v, n))); v \\ Nick Hobson, Nov 29 2006
CROSSREFS
Sequence in context: A332269 A328338 A365535 * A036436 A036455 A291127
KEYWORD
easy,nonn
AUTHOR
Giovanni Teofilatto, Aug 06 2006
EXTENSIONS
More terms from Nick Hobson, Nov 29 2006
Incorrect comment removed by Charles R Greathouse IV, Mar 25 2010
STATUS
approved

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Last modified March 28 20:05 EDT 2024. Contains 371254 sequences. (Running on oeis4.)