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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

Table of n, a(n) for n=1..14.

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 October 21 08:00 EDT 2018. Contains 316405 sequences. (Running on oeis4.)