A165924 a(n) = number of squareful nonzero quadratic residues of n.

0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 3, 3, 2, 2, 4, 3, 3, 3, 4, 5, 6, 4, 4, 5, 4, 5, 7, 5, 8, 4, 6, 7, 4, 5, 8, 8, 7, 7, 10, 7, 7, 7, 6, 11, 12, 5, 9, 8, 7, 9, 11, 10, 9, 10, 10, 12, 12, 9, 14, 15, 8, 6, 9, 12, 12, 11, 14, 11, 20, 10, 17, 14, 9, 13, 10, 13, 18, 8, 12, 17, 17, 11, 12, 17

Offset: 1

Author

Christopher Hunt Gribble, Sep 30 2009

Keywords

• nonn

Links

• C. H. Gribble, Table of n, a(n) for n=1..1000.

Crossrefs

Cf. A165919.