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Numbers n such that bigomega(sigma(n))=bigomega(n).
1

%I #15 Apr 21 2014 08:29:50

%S 1,2,12,20,24,40,45,49,52,75,90,98,104,108,117,121,148,150,169,216,

%T 224,234,242,244,252,292,296,325,333,336,338,352,361,368,396,480,488,

%U 500,504,528,529,544,549,560,567,584,588,608,612,628,650,657,666,675,684

%N Numbers n such that bigomega(sigma(n))=bigomega(n).

%C So, also numbers such that bigomega(numerator(sigma(n)/n)) = bigomega(denominator(sigma(n)/n)), that is, A001222(A017665(n)) = A001222(A017666(n)). - _Michel Marcus_, Apr 20 2014

%H Vincenzo Librandi, <a href="/A067762/b067762.txt">Table of n, a(n) for n = 1..1000</a>

%t Select[Range[1000],PrimeOmega[DivisorSigma[1,#]]==PrimeOmega[#]&] (* _Harvey P. Dale_, Oct 15 2012 *)

%Y Cf. A000203, A001222.

%K nonn

%O 1,2

%A _Benoit Cloitre_, Feb 06 2002