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A189716 Numbers k such that A156595(k-1) = 1; complement of A189715. 10
2, 3, 5, 8, 11, 12, 14, 17, 18, 20, 21, 23, 26, 27, 29, 30, 32, 35, 38, 39, 41, 44, 45, 47, 48, 50, 53, 56, 57, 59, 62, 65, 66, 68, 71, 72, 74, 75, 77, 80, 83, 84, 86, 89, 92, 93, 95, 98, 99, 101, 102, 104, 107, 108, 110, 111, 113, 116, 119, 120, 122, 125, 126, 128, 129, 131, 134, 137, 138, 140, 143, 146, 147, 149, 152, 153, 155, 156, 158 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
See A156595.
Numbers whose squarefree part is congruent modulo 9 to 2, 3, 5 or 8. - Peter Munn, May 17 2020
The asymptotic density of this sequence is 1/2. - Amiram Eldar, Mar 08 2021
LINKS
MATHEMATICA
(See A189715.)
f[p_, e_] := (p^Mod[e, 2]); sqfpart[n_] := Times @@ f @@@ FactorInteger[n]; Select[Range[160], MemberQ[{2, 3, 5, 8}, Mod[sqfpart[#], 9]] &] (* Amiram Eldar, Mar 08 2021 *)
CROSSREFS
Union of A055041 and A055048.
Sequence in context: A276731 A028891 A028890 * A002480 A173672 A303024
KEYWORD
nonn
AUTHOR
Clark Kimberling, Apr 26 2011
EXTENSIONS
Name enhanced by Peter Munn, May 17 2020
STATUS
approved

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Last modified April 24 17:51 EDT 2024. Contains 371962 sequences. (Running on oeis4.)