A123314 Number of times the n-th squarefree number occurs as maximal greatest common divisor of pairs of distinct squarefree numbers.

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

Offset: 1

Author

Reinhard Zumkeller, Sep 25 2006

Keywords

• nonn

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.

Formula

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