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A169646 Number of squarefree numbers of form k*n, 1<=k<=n. 0
1, 1, 2, 0, 3, 2, 5, 0, 0, 3, 7, 0, 8, 5, 6, 0, 11, 0, 12, 0, 8, 9, 15, 0, 0, 10, 0, 0, 17, 8, 19, 0, 13, 13, 15, 0, 23, 15, 17, 0, 26, 11, 28, 0, 0, 18, 30, 0, 0, 0, 21, 0, 32, 0, 25, 0, 23, 23, 36, 0, 37, 25, 0, 0, 30, 18, 41, 0, 29, 22, 44, 0, 45, 30, 0, 0, 36, 22, 49, 0, 0, 32, 51, 0, 41, 34 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

a(n) = A008966(n)*A073311(n);

a(A000040(n)) = A112929(n).

LINKS

Table of n, a(n) for n=1..86.

MATHEMATICA

Count[#, _?SquareFreeQ]&/@Table[k*n, {n, 90}, {k, n}] (* Harvey P. Dale, Sep 05 2012 *)

CROSSREFS

Sequence in context: A008807 A263149 A008819 * A231117 A021496 A241830

Adjacent sequences:  A169643 A169644 A169645 * A169647 A169648 A169649

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Apr 05 2010

STATUS

approved

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Last modified December 2 19:13 EST 2016. Contains 278683 sequences.