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%I #9 Jul 23 2014 12:02:30
%S 1,3,7,7,13,13,19,19,31,31,31,31,43,43,43,43,61,61,61,61,67,67,67,67,
%T 91,91,91,91,91,91,91,91,121,121,121,121,127,127,127,127,151,151,151,
%U 151,151,151,151,151,211,211,211,211,211,211,211,211,211,211,211,211,211
%N Least m such that k>=m implies phi(k)>=n (where phi is the Euler totient function, sequence A000010).
%C Define b(n)=A006511(m)+1 where m is the unique integer such that A002202(m)<n<=A002202(m+1) (with the convention A002202(0)=A006511(0)=0). Then a(1)=b(1) and a(n+1)=max(a(n),b(n+1)).
%C The sequence a(n) without the repetitions is 1+A036913(n).
%H Max Alekseyev, <a href="/A139795/b139795.txt">Table of n, a(n) for n = 1..10000</a>
%H Max Alekseyev, <a href="http://home.gwu.edu/~maxal/gpscripts/">PARI scripts for various problems</a> (see invphi.gp there).
%e a(5)=13 because if k>=13, then phi(k)>=5, but phi(12)=4.
%o (PARI) {m=0;for(n=1,100,print1(m+1,",");trap(,0,m=max(m,vecmax(invphi(n)))))}
%Y Different from A137315 (see Comments in that entry).
%K nonn
%O 1,2
%A _Benoit Jubin_, May 21 2008
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