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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, 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
CROSSREFS
Cf. A036997 (phi(n) - max(phi(c, n)) over all nonnegative integers c)
Sequence in context: A345388 A322983 A208459 * A084929 A293575 A054014
KEYWORD
easy,nonn
AUTHOR
Reikku Kulon, Sep 20 2008
STATUS
approved