This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A064517 #12 Jun 20 2018 01:29:56
%S A064517 1,2,7,8,9,10,23,24,25,26,27,28,53,54,55,56,57,58,97,98,99,100,151,
%T A064517 152,153,154,155,156,227,228,311,312,419,420,541,542,543,544,545,546,
%U A064517 661,662,663,664,665,666,667,668,669,670,671,672,827,828,1009,1010,1011
%N A064517 Numbers k such that pi(k) is a square.
%H A064517 Harry J. Smith, <a href="/A064517/b064517.txt">Table of n, a(n) for n = 1..1000</a>
%o A064517 (PARI) pi(x, c=0) = forprime(p=2,x,c++); c for(n=1,2000, if(issquare(pi(n)),print1(n," ")))
%o A064517 (PARI) { n=0; for (m=1, 10^9, if (issquare(primepi(m)), write("b064517.txt", n++, " ", m); if (n==1000, break)) ) } \\ _Harry J. Smith_, Sep 17 2009
%Y A064517 Cf. A000720.
%K A064517 easy,nonn
%O A064517 1,2
%A A064517 _Jason Earls_, Oct 07 2001