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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 MATHEMATICA Count[#, _?SquareFreeQ]&/@Table[k*n, {n, 90}, {k, n}] (* Harvey P. Dale, Sep 05 2012 *) CROSSREFS Sequence in context: A008819 A279591 A279675 * 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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