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a(n) is the largest number in the set of solutions to n=x/pi(x), where pi(x)=A000720(x).
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%I #23 Sep 04 2018 09:27:43

%S 8,33,120,360,1134,3094,8472,24300,64720,175197,481452,1304719,

%T 3524654,9560100,25874784,70119985,189969354,514278263,1394199300,

%U 3779856633,10246936436,27788573803,75370126416,204475055200,554805820556,1505578026105,4086199303004,11091501633037

%N a(n) is the largest number in the set of solutions to n=x/pi(x), where pi(x)=A000720(x).

%H Giovanni Resta, <a href="/A087235/b087235.txt">Table of n, a(n) for n = 2..50</a>

%H Robert T. Harger and William L. Hightower, <a href="http://www.jstor.org/stable/25653721">An Interesting Property of x/π(x)</a>, The College Mathematics Journal Vol. 40, No. 3 (May 2009), pp. 213-214.

%F a(n) = Max{x; n*pi(x)=x}.

%e n=22: list of solutions = {10246935644, 10246935842, 10246935864, 10246935974, 10246936106, 10246936128, 10246936370, 10246936436}, so a(22)=10246936436.

%Y Cf. A038623, A038624, A038625, A038626, A038627, A057809.

%K nonn

%O 2,1

%A _Labos Elemer_, Sep 04 2003

%E More terms from _David Radcliffe_, Sep 10 2014

%E a(29) corrected and a(30)-a(50) obtained from the values of A038625 computed by _Jan Büthe_. - _Giovanni Resta_, Sep 01 2018