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%I #17 Jun 18 2024 17:51:03
%S 27,45,63,75,99,105,117,125,147,153,165,171,175,195,207,231,243,245,
%T 255,261,273,275,279,285,325,333,343,345,357,363,369,385,387,399,405,
%U 423,425,429,435,455,465,475,477,483,507,531,539,549,555,561,567,575
%N Odd composite numbers with an odd number of prime factors (counted with multiplicity).
%H John Cerkan, <a href="/A046340/b046340.txt">Table of n, a(n) for n = 1..10000</a>
%t Select[Range[3,699,2],OddQ[Total[Transpose[FactorInteger[#]][[2]]]] && !PrimeQ[#]&] (* _Harvey P. Dale_, Dec 09 2010 *)
%t Select[Range[3,699,2],CompositeQ[#]&&OddQ[PrimeOmega[#]]&] (* _Harvey P. Dale_, Jun 18 2024 *)
%Y Cf. A046339, A046341.
%K nonn
%O 1,1
%A _Patrick De Geest_, Jun 15 1998
%E Name (description) modified by _Harvey P. Dale_, Dec 09 2010