A144764 Partial totient function phi(c, n) for c = 3: number of 3-semiprimes less than and coprime to n.

0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 2, 0, 1, 0, 2, 0, 3, 0, 2, 0, 4, 0, 3, 0, 2, 1, 6, 0, 7, 1, 3, 1, 4, 0, 7, 1, 3, 1, 7, 0, 8, 1, 3, 2, 10, 0, 8, 1, 5, 2, 12, 0, 7, 2, 6, 2, 12, 0, 12, 2, 5, 3, 8, 0, 14, 3, 7, 1, 16, 0, 16, 3, 5, 4, 12, 0, 19, 2, 9, 4, 19, 0, 12, 4, 9, 4, 19, 0, 13, 4, 10, 4, 13, 0, 20, 3

Offset

1,13

Links

Table of n, a(n) for n=1..98.

Crossrefs

Cf. A000010, A014612, A144740

Cf. A036997 (phi(n) - max(phi(c, n)) over all nonnegative integers c)

Sequence in context: A345388 A322983 A208459 * A084929 A293575 A054014

Adjacent sequences: A144761 A144762 A144763 * A144765 A144766 A144767

Keyword

easy,nonn

Author

Reikku Kulon, Sep 20 2008

Status

approved