A123314 - OEIS

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A123314

Number of times the n-th squarefree number occurs as maximal greatest common divisor of pairs of distinct squarefree numbers.

3

4, 0, 2, 3, 0, 5, 0, 2, 2, 0, 3, 3, 3, 2, 0, 6, 0, 3, 0, 2, 3, 0, 3, 2, 0, 2, 3, 0, 5, 0, 4, 3, 3, 3, 2, 0, 2, 4, 0, 3, 0, 2, 3, 0, 3, 3, 0, 3, 0, 5, 0, 2, 2, 0, 2, 3, 3, 2, 0, 3, 5, 3, 0, 2, 3, 0, 3, 3, 0, 2, 3, 0, 5, 0, 3, 0, 5, 3, 2, 0, 3, 5, 0, 2, 0, 2, 3, 0, 2, 4, 0, 3, 5, 0, 3, 2, 0, 3, 2, 3, 2, 0, 6, 0, 4

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OFFSET

1,1

COMMENTS

a(n) > 0 iff A005117(n) is an odd squarefree number: a(A100112(A056911(n)))>0;

a(n) = 0 iff A005117(n) is an even squarefree number: a(A100112(A039956(n)))=0.

LINKS

Table of n, a(n) for n=1..105.

FORMULA

a(n) = #{k: A123313(k) = A005117(n)}.

CROSSREFS

Sequence in context: A180850 A109157 A226955 * A058997 A261164 A323982

Adjacent sequences: A123311 A123312 A123313 * A123315 A123316 A123317

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Sep 25 2006

STATUS

approved