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A189716 Numbers k such that A156595(k-1) = 1; complement of A189715. 6
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

Amiram Eldar, Table of n, a(n) for n = 1..10000

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

Cf. A007913, A156595, A189715, A189717.

Union of A055041 and A055048.

Sequence in context: A276731 A028891 A028890 * A002480 A173672 A303024

Adjacent sequences:  A189713 A189714 A189715 * A189717 A189718 A189719

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 January 26 07:28 EST 2022. Contains 350577 sequences. (Running on oeis4.)