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A072076 Largest k such that EulerPhihi(k) = 10^n. 3
2, 22, 250, 3750, 41250, 414150, 4166250, 42281250, 438281250, 4400343750, 44266406250, 449238281250, 4510352343750, 45373066406250, 455545586718750, 4555455867187500, 45555287544813750, 455552875448137500 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Ray Chandler, Table of n, a(n) for n = 0..1000

Max A. Alekseyev, Computing the Inverses, their Power Sums, and Extrema for Euler's Totient and Other Multiplicative Functions. Journal of Integer Sequences, Vol. 19 (2016), Article 16.5.2

FORMULA

a(n) = Max{k; A000010(k) = 10^n}.

EXAMPLE

n=3: a(3)=3750 because InvPhi(1000) = {1111, 1255, 1375, 1875, 2008, 2222, 2500, 2510, 2750, 3012, 3750}.

CROSSREFS

Cf. A000010, A014197, A014573, A072074, A072075, A110076.

Sequence in context: A151617 A082777 A229465 * A226706 A036841 A264836

Adjacent sequences:  A072073 A072074 A072075 * A072077 A072078 A072079

KEYWORD

nonn

AUTHOR

Labos Elemer, Jun 13 2002

EXTENSIONS

More terms from Max Alekseyev, Apr 26 2010

STATUS

approved

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Last modified September 26 01:25 EDT 2017. Contains 292500 sequences.