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A304364 Numbers n such that A304362(n) = Sum_{d|n, d = 1 or not a perfect power} mu(n/d) = 0. 4
2, 3, 5, 6, 7, 8, 10, 11, 13, 14, 15, 16, 17, 19, 21, 22, 23, 24, 26, 27, 29, 30, 31, 32, 33, 34, 35, 37, 38, 39, 40, 41, 42, 43, 46, 47, 48, 51, 53, 54, 55, 56, 57, 58, 59, 61, 62, 64, 65, 66, 67, 69, 70, 71, 73, 74, 77, 78, 79, 80, 81, 82, 83, 85, 86, 87, 88 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Also numbers n such that mu(n) = -Sum_{d|n, d not a perfect power} mu(n/d).

Contains all squarefree numbers (A005117) except 1.

LINKS

Andrew Howroyd, Table of n, a(n) for n = 1..1000

MATHEMATICA

Select[Range[100], Sum[If[GCD@@FactorInteger[d][[All, 2]]===1, MoebiusMu[#/d], 0], {d, Divisors[#]}]===0&]

PROG

(PARI) ok(n)={sumdiv(n, d, if(ispower(d), 0, moebius(n/d))) == 0} \\ Andrew Howroyd, Aug 26 2018

CROSSREFS

Cf. A000005, A000961, A001221, A001597, A001694, A005117, A007916, A008683, A091050, A304326, A304327, A304362, A304365, A304369.

Sequence in context: A028749 A028764 A326070 * A000452 A307295 A047587

Adjacent sequences:  A304361 A304362 A304363 * A304365 A304366 A304367

KEYWORD

nonn

AUTHOR

Gus Wiseman, May 11 2018

STATUS

approved

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Last modified October 23 03:21 EDT 2019. Contains 328335 sequences. (Running on oeis4.)