login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A046340 Odd composite numbers with an odd number of prime factors (counted with multiplicity). 4

%I #13 Apr 12 2017 23:31:13

%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 *)

%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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 18 20:26 EDT 2024. Contains 371781 sequences. (Running on oeis4.)