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A048106 Number of unitary divisors of n (A034444) - number of non-unitary divisors of n (A048105). 2
1, 2, 2, 1, 2, 4, 2, 0, 1, 4, 2, 2, 2, 4, 4, -1, 2, 2, 2, 2, 4, 4, 2, 0, 1, 4, 0, 2, 2, 8, 2, -2, 4, 4, 4, -1, 2, 4, 4, 0, 2, 8, 2, 2, 2, 4, 2, -2, 1, 2, 4, 2, 2, 0, 4, 0, 4, 4, 2, 4, 2, 4, 2, -3, 4, 8, 2, 2, 4, 8, 2, -4, 2, 4, 2, 2, 4, 8, 2, -2, -1, 4, 2, 4, 4, 4, 4, 0, 2, 4, 4, 2, 4, 4, 4, -4, 2, 2, 2 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

FORMULA

a[ n ]=2^(1+r(n)) - d(n) =2^(1+A001221(n))-A000005(n).

a(n) = -Sum_{ d divides n } (-1)^mu(d). - Vladeta Jovovic (vladeta(AT)eunet.rs), Jan 24 2002

CROSSREFS

Cf. A008683.

Sequence in context: A125912 A127677 A007427 * A156260 A056671 A055076

Adjacent sequences:  A048103 A048104 A048105 * A048107 A048108 A048109

KEYWORD

sign

AUTHOR

Labos E. (labos(AT)ana.sote.hu)

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Last modified February 15 18:11 EST 2012. Contains 205835 sequences.