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%I #15 Mar 24 2019 06:11:01
%S 4,7,22,83,5878,12229,14871,43360,120833116,284116756,384239518,
%T 586968768,2697787565123,11550434172799,65612899915231,
%U 252252704148332,2105877470620834,36504944044141057,4194084944223361535
%N Numbers k such that prime(k) = A123206(n).
%H Kim Walisch, <a href="https://github.com/kimwalisch/primecount">Fast C++ prime counting function implementation (primecount)</a>.
%F a(n) = A000720(A123206(n)).
%Y Cf. A000720, A123206.
%K hard,more,nonn
%O 1,1
%A _Alexander Adamchuk_, Mar 03 2007
%E a(13)-a(14) from _Max Alekseyev_, Feb 23 2012
%E a(15)-a(19) using Kim Walisch's primecount, from _Amiram Eldar_, Mar 24 2019