|
|
A046340
|
|
Odd composite numbers with an odd number of prime factors (counted with multiplicity).
|
|
4
|
|
|
27, 45, 63, 75, 99, 105, 117, 125, 147, 153, 165, 171, 175, 195, 207, 231, 243, 245, 255, 261, 273, 275, 279, 285, 325, 333, 343, 345, 357, 363, 369, 385, 387, 399, 405, 423, 425, 429, 435, 455, 465, 475, 477, 483, 507, 531, 539, 549, 555, 561, 567, 575
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
LINKS
|
|
|
MATHEMATICA
|
Select[Range[3, 699, 2], OddQ[Total[Transpose[FactorInteger[#]][[2]]]] && !PrimeQ[#]&] (* Harvey P. Dale, Dec 09 2010 *)
Select[Range[3, 699, 2], CompositeQ[#]&&OddQ[PrimeOmega[#]]&] (* Harvey P. Dale, Jun 18 2024 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|