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A171521
Numbers that are not the product of k-th composite number and k for any k >= 1.
1
1, 2, 3, 5, 6, 7, 8, 9, 10, 11, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 73, 74, 75
OFFSET
1,2
COMMENTS
Complement of A071228.
MATHEMATICA
Module[{nn=150, cmps}, cmps=Select[Range[nn], CompositeQ]; Complement[ Range[ Length[cmps]], Times@@@Thread[{cmps, Range[Length[cmps]]}]]] (* Harvey P. Dale, Jan 21 2023 *)
CROSSREFS
Sequence in context: A081023 A165332 A031179 * A352796 A092784 A047588
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Dec 11 2009
EXTENSIONS
More terms from Hugo Pfoertner, Jan 17 2022
STATUS
approved