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 A071973 #18 Oct 09 2020 03:49:17
%S A071973 0,2,4,11,25,62,162,433,1175,3229,9042,25549,73050,210356,610041,
%T A071973 1779830,5218745,15372304,45455747,134882577,401480918,1198344171,
%U A071973 3585783711,10754085805,32319203663,97312548674,293515297707,886720888966,2682778745396,8127887397064
%N A071973 Number of primes less than or equal to Pi^n.
%H A071973 David Baugh, <a href="/A071973/b071973.txt">Table of n, a(n) for n = 0..52</a> (terms n = 27..52 found using Kim Walisch's primecount program)
%H A071973 <a href="/index/Pri#primepop">Index entries for sequences related to numbers of primes in various ranges</a>
%F A071973 a(n) = A000720(A001672(n)). - _Michel Marcus_, Oct 05 2020
%t A071973 Do[ Print[ PrimePi[Pi^n]], {n, 0, 28}]
%o A071973 (PARI) a(n) = primepi(Pi^n); \\ _Michel Marcus_, Oct 05 2020
%Y A071973 Cf. A000720, A001672, A061274.
%K A071973 hard,nonn
%O A071973 0,2
%A A071973 _Robert G. Wilson v_, Jun 18 2002
%E A071973 a(27)-a(29) from _David Baugh_, Oct 05 2020