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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

John Cerkan, Table of n, a(n) for n = 1..10000

MATHEMATICA

Select[Range[3, 699, 2], OddQ[Total[Transpose[FactorInteger[#]][[2]]]] && !PrimeQ[#]&] (* Harvey P. Dale, Dec 09 2010 *)

CROSSREFS

Cf. A046339, A046341.

Sequence in context: A253919 A259504 A121614 * A046316 A046373 A228057

Adjacent sequences:  A046337 A046338 A046339 * A046341 A046342 A046343

KEYWORD

nonn

AUTHOR

Patrick De Geest, Jun 15 1998

EXTENSIONS

Name (description) modified by Harvey P. Dale, Dec 09 2010

STATUS

approved

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Last modified February 21 11:36 EST 2019. Contains 320372 sequences. (Running on oeis4.)