%I #17 Jan 13 2020 11:29:11
%S 2,6,30,210,30030,223092870,13082761331670030,
%T 3217644767340672907899084554130,
%U 1492182350939279320058875736615841068547583863326864530410
%N Least number k such that n * phi(k) < k, where phi is Euler's totient function.
%C By Mertens' theorem and the Prime Number Theorem log log a(n) ~ n / e^gamma. - _Charles R Greathouse IV_, Sep 07 2012
%o (PARI) a(n) = {k = 1; while (n*eulerphi(k) >= k, k++); k;} \\ _Michel Marcus_, Sep 25 2013
%o (PARI) a(n)=my(k=1);forprime(p=2,,if(n*eulerphi(k)<k,return(k),k*=p)) \\ _Charles R Greathouse IV_, Sep 25 2013
%Y Subsequence of A002110. Cf. A000010, A054741, A073087, A091439 (n * phi(k) <= k).
%K nonn
%O 1,1
%A _Robert G. Wilson v_, Jan 10 2004
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