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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; internal format)
OFFSET

1,1

COMMENTS

a(15) <= 1625589504000. a(16) <= 26009432064000. a(17) <= 442160345088000. [From Donovan Johnson (donovan.johnson(AT)yahoo.com), Feb 05 2010]

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: A038077 A006396 A192502 * A002577 A076132 A047142

Adjacent sequences:  A066275 A066276 A066277 * A066279 A066280 A066281

KEYWORD

nonn

AUTHOR

Labos E. (labos(AT)ana.sote.hu), Dec 10 2001

EXTENSIONS

a(12)-a(14) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Feb 05 2010

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Last modified February 17 22:48 EST 2012. Contains 206085 sequences.