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A066278
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Least solution to cototient[x] = x-Phi[x] = n!.
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0
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2, 4, 10, 36, 168, 1008, 7056, 56448, 470400, 4704000, 51528960, 618347520, 7740902400, 108372633600
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OFFSET
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1,1
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COMMENTS
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a(15) <= 1625589504000. a(16) <= 26009432064000. a(17) <= 442160345088000. [From Donovan Johnson, Feb 05 2010]
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LINKS
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Table of n, a(n) for n=1..14.
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FORMULA
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a(n)=Min{x; x-A000010(x)=n!} = Min{A051953(x)=A000142(n)}
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EXAMPLE
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Solutions to x-Phi[x]=720 are {1008,1424,1432,1436,1438} of which the smallest is a(6)=1008.
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CROSSREFS
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Cf. A000010, A051953, A000142, A055487.
Sequence in context: A038077 A006396 A192502 * A210773 A210774 A210775
Adjacent sequences: A066275 A066276 A066277 * A066279 A066280 A066281
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KEYWORD
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nonn
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AUTHOR
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Labos E. (labos(AT)ana.sote.hu), Dec 10 2001
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EXTENSIONS
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a(12)-a(14) from Donovan Johnson, Feb 05 2010
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STATUS
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approved
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