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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 (list; graph; refs; listen; history; text; internal format)
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: A230642 A053473 A208459 * A084929 A054014 A158945

Adjacent sequences:  A144761 A144762 A144763 * A144765 A144766 A144767

KEYWORD

easy,nonn

AUTHOR

Reikku Kulon, Sep 20 2008

STATUS

approved

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Last modified December 7 07:15 EST 2016. Contains 278841 sequences.