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A120497 Positive integers whose number of divisors is a perfect power. 0

%I #10 Oct 19 2022 10:04:56

%S 1,6,8,10,14,15,21,22,24,26,27,30,33,34,35,36,38,39,40,42,46,51,54,55,

%T 56,57,58,62,65,66,69,70,74,77,78,82,85,86,87,88,91,93,94,95,100,102,

%U 104,105,106,110,111,114,115,118,119,120,122,123,125,128,129,130,133,134

%N Positive integers whose number of divisors is a perfect power.

%t Join[{1},Select[Range[150],GCD@@FactorInteger[DivisorSigma[0,#]][[All,2]]>1&]] (* _Harvey P. Dale_, Oct 19 2022 *)

%o (PARI) v=[1]; for(n=2, 134, if(ispower(numdiv(n)), v=concat(v, n))); v \\ Nick Hobson, Nov 29 2006

%K easy,nonn

%O 1,2

%A _Giovanni Teofilatto_, Aug 06 2006

%E More terms from Nick Hobson, Nov 29 2006

%E Incorrect comment removed by _Charles R Greathouse IV_, Mar 25 2010

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Last modified August 29 15:03 EDT 2024. Contains 375517 sequences. (Running on oeis4.)