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A074701
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Numbers n such that n = sum( d dividing phi(n), mu(phi(d))*phi(n)/d ).
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2
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OFFSET
| 1,2
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COMMENTS
| Does sequence consist of 1,3 and all powers of 5? Answer from Lambert Klasen, Oct 07 2005: Yes! See attached file.
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LINKS
| Lambert Klasen, Notes on A074701
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MAPLE
| with(numtheory): a:=proc(n) local div: div:=convert(divisors(phi(n)), list): if add(mobius(phi(div[j]))*phi(n)/div[j], j=1..nops(div))=n then n else fi end: seq(a(n), n=1..5000); (Deutsch)
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CROSSREFS
| Cf. A000351. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Sep 23 2008]
Sequence in context: A200948 A009002 A119882 * A140127 A154143 A101611
Adjacent sequences: A074698 A074699 A074700 * A074702 A074703 A074704
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KEYWORD
| more,nonn
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AUTHOR
| Benoit Cloitre (benoit7848c(AT)orange.fr), Sep 03 2002
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EXTENSIONS
| 2 more terms from Emeric Deutsch (deutsch(AT)duke.poly.edu), Mar 27 2005
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