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Search: id:A073312
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A073312 Number of non square-free numbers in the reduced residue system of n. +0
2
0, 0, 0, 0, 1, 0, 1, 0, 2, 1, 3, 0, 4, 1, 2, 1, 5, 0, 6, 1, 4, 1, 7, 0, 7, 2, 5, 3, 11, 0, 11, 3, 7, 3, 9, 1, 13, 3, 7, 2, 14, 1, 14, 3, 6, 4, 16, 1, 16, 3, 11, 5, 20, 2, 15, 4, 13, 5, 22, 1, 23, 5, 10, 6, 18, 2, 25, 6, 15, 2, 26, 2, 27, 6, 11, 7, 24, 2, 29, 4, 17, 8, 31, 1, 23, 8, 17, 8, 33, 1, 28 (list; graph; listen)
OFFSET

1,9

COMMENT

a(n) + A073311(n) = A000010(n).

EXAMPLE

n=15, there are A000005(15)=8 residues: 1, 2, 4=2^2, 7, 8=2^3, 11, 13, and 14; two of them are not square-free: 4 and 8, therefore a(15)=2.

CROSSREFS

Cf. A073311, A013929, A000010, A048864, A048865.

Adjacent sequences: A073309 A073310 A073311 this_sequence A073313 A073314 A073315

Sequence in context: A141198 A092093 A096269 this_sequence A081171 A062778 A108202

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Jul 25 2002

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Last modified October 13 20:18 EDT 2008. Contains 145016 sequences.


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