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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
OFFSET
1,1
LINKS
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
KEYWORD
nonn
AUTHOR
EXTENSIONS
Corrected (45 inserted, 109 removed, 146 replaced with 146 etc.) by R. J. Mathar, May 05 2010
STATUS
approved