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A155082 Composites k such that the number of prime factors of composite(k) (counted with multiplicity) is composite. 1
9, 14, 24, 27, 39, 42, 45, 58, 60, 64, 65, 74, 76, 95, 99, 102, 105, 114, 115, 119, 122, 141, 146, 152, 168, 172, 175, 176, 178, 182, 187, 194, 196, 201, 204, 217, 231, 234, 243, 244, 249, 261, 268, 273, 275, 278, 279, 280, 287, 291, 298, 300, 301, 304, 312 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Muniru A Asiru, Table of n, a(n) for n = 1..10000

EXAMPLE

9 (composite) is a term because composite(9) = 16 = 2*2*2*2 (4 prime factors);

14 (composite) is a term because composite(14) = 24 = 2*2*2*3 (4 prime factors);

24 (composite) is a term because composite(24) = 36 = 2*2*3*3 (4 prime factors).

PROG

(GAP) A:=Filtered([2..500], n->not IsPrime(n));;

B:=List(List(A, Factors), Length);;

a:=Filtered([1..Length(B)], i->B[i] in A and not IsPrime(i)); # Muniru A Asiru, Feb 10 2019

CROSSREFS

Cf. A000040, A002808, A001222.

Sequence in context: A001198 A151915 A100263 * A161547 A104812 A329751

Adjacent sequences:  A155079 A155080 A155081 * A155083 A155084 A155085

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov, Jan 20 2009

EXTENSIONS

Corrected (45 inserted, 109 removed, 146 replaced with 146 etc.) by R. J. Mathar, May 05 2010

STATUS

approved

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Last modified April 10 17:00 EDT 2021. Contains 342852 sequences. (Running on oeis4.)