%I #24 Jul 19 2016 16:22:04

%S 1,11,101,1111,10291,100651,1004251,10165751,100064101,1000078501,

%T 10000222501,100062501601,1000062516001,10000062660001,

%U 100002441447211,1003922328562757,10000390625025601,100000002482366251,1000000002851006251,10000062500000160001

%N Smallest solution to phi(x) = 10^n where phi(x) = A000010(x).

%H Ray Chandler, <a href="/A072075/b072075.txt">Table of n, a(n) for n = 0..1000</a>

%H Max A. Alekseyev, <a href="https://www.emis.de/journals/JIS/VOL19/Alekseyev/alek5.html">Computing the Inverses, their Power Sums, and Extrema for Euler's Totient and Other Multiplicative Functions</a>. Journal of Integer Sequences, Vol. 19 (2016), Article 16.5.2

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

%Y Cf. A000010, A014573, A014197, A110077, A072074, A072076.

%K nonn

%O 0,2

%A _Labos Elemer_, Jun 13 2002

%E More terms from _Max Alekseyev_, Apr 26 2010

%E a(18)-a(19) from _Donovan Johnson_, Feb 02 2012