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 A066278 Least solution to cototient[x] = x-Phi[x] = n!. 0
 2, 4, 10, 36, 168, 1008, 7056, 56448, 470400, 4704000, 51528960, 618347520, 7740902400, 108372633600 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(15) <= 1625589504000. a(16) <= 26009432064000. a(17) <= 442160345088000. [From Donovan Johnson, Feb 05 2010] LINKS FORMULA a(n)=Min{x; x-A000010(x)=n!} = Min{A051953(x)=A000142(n)} EXAMPLE Solutions to x-Phi[x]=720 are {1008,1424,1432,1436,1438} of which the smallest is a(6)=1008. CROSSREFS Cf. A000010, A051953, A000142, A055487. Sequence in context: A006396 A192502 A243567 * A210773 A210774 A210775 Adjacent sequences:  A066275 A066276 A066277 * A066279 A066280 A066281 KEYWORD nonn AUTHOR Labos Elemer, Dec 10 2001 EXTENSIONS a(12)-a(14) from Donovan Johnson, Feb 05 2010 STATUS approved

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Last modified January 16 15:31 EST 2019. Contains 319195 sequences. (Running on oeis4.)