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%I #46 Jun 12 2020 04:23:25
%S 157,991,1217,7057,7523,7649,7841,9293,9661,9833,9923,10009,10079,
%T 10457,10487,11447,11927,12301,12547,12763,13469,13513,13693,14177,
%U 15511,15683,30557,31033,31069,31267,31277,32299,32341,32911,33029,35363,35801,72559,73453
%N Emirp-indexed emirps: emirps with emirp subscripts.
%C Here the 'subscript' of an emirp is the index of it over all the primes, not over the emirps (otherwise we would get {A006567(A006567(n))} sorted). - _Jianing Song_, Oct 29 2019
%H Metin Sariyar, <a href="/A326442/b326442.txt">Table of n, a(n) for n = 1..10000</a>
%H Chris K. Caldwell and G. L. Honaker, Jr., <a href="https://primes.utm.edu/curios/page.php?curio_id=29363">Prime curio for 157</a>
%e 157 is a term because 157, 751, pi(157) = 37 and 73 are all primes.
%t Do[y=IntegerReverse;z=PrimeQ;k=PrimePi[n];a=y[n];b=y[k];If[!a==n&&!b==k&&z[a]&&z[b]&&z[n]&&z[k],Print[n]],{n,1,10^5}]
%o (PARI) is_emirps(n) = my(r=eval(concat(Vecrev(Str(n))))); isprime(r)&&r!=n&&isprime(n); \\ A006567
%o isok(n) = is_emirps(n) && is_emirps(primepi(n)); \\ _Michel Marcus_, Oct 14 2019
%Y Cf. A006450, A006567.
%K nonn,base
%O 1,1
%A _Metin Sariyar_, Oct 09 2019
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