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

1,10

Links

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

Crossrefs

Cf. A165919.

Sequence in context: A098014 A059957 A361088 * A212628 A272851 A242258

Adjacent sequences: A165921 A165922 A165923 * A165925 A165926 A165927

Keyword

nonn

Author

Christopher Hunt Gribble, Sep 30 2009

Status

approved