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A076545 sum[k=1 to n] mu(k)+sqf(k): mu(k) is Moebius function; sqf(k)=1 if k is squarefree, sqf(k)=-1 otherwise. 0
2, 2, 2, 1, 1, 3, 3, 2, 1, 3, 3, 2, 2, 4, 6, 5, 5, 4, 4, 3, 5, 7, 7, 6, 5, 7, 6, 5, 5, 5, 5, 4, 6, 8, 10, 9, 9, 11, 13, 12, 12, 12, 12, 11, 10, 12, 12, 11, 10, 9, 11, 10, 10, 9, 11, 10, 12, 14, 14, 13, 13, 15, 14, 13, 15, 15, 15, 14, 16, 16, 16, 15, 15, 17, 16, 15, 17, 17, 17, 16, 15 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
MATHEMATICA
Accumulate[Table[MoebiusMu[n]+If[SquareFreeQ[n], 1, -1], {n, 100}]] (* Harvey P. Dale, Jun 02 2022 *)
CROSSREFS
Sequence in context: A098593 A144431 A053821 * A162246 A277447 A333698
KEYWORD
easy,nonn
AUTHOR
Zak Seidov, Oct 19 2002
STATUS
approved

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Last modified April 22 18:29 EDT 2024. Contains 371906 sequences. (Running on oeis4.)