A144765 Partial cototient function Phi(c, n) for c = 3: number of 3-semiprimes less than or equal and not coprime to n.

0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 2, 0, 2, 1, 2, 0, 3, 0, 4, 2, 4, 0, 4, 1, 4, 3, 5, 0, 7, 0, 6, 4, 6, 3, 7, 0, 6, 4, 6, 0, 8, 0, 8, 7, 8, 0, 10, 2, 10, 6, 10, 0, 12, 5, 10, 6, 10, 0, 12, 0, 10, 8, 10, 5, 14, 0, 12, 8, 15, 0, 16, 0, 13, 12, 14, 6, 19, 0, 17, 10, 15, 0, 19, 7, 15, 10, 15, 0, 19, 6, 16