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 A126137 #18 Jun 05 2025 00:42:02
%S A126137 1,2,4,8,16,35,79,184,429,1019,2467,6049,14912,37128,93117,234855,
%T A126137 595341,1516234,3877186,9950346,25614563,66124777,171141897,443963543,
%U A126137 1154106845,3005936865,7842921261,20496470802,53645077679,140599114669,368973074566,969455391691
%N A126137 a(n) = pi(A037028(n)).
%H A126137 Amiram Eldar, <a href="/A126137/b126137.txt">Table of n, a(n) for n = 0..52</a>
%e A126137 a(3) = 8 since A037028(3) = 19 and 19 = the 8th prime.
%e A126137 a(4) = 16 since A037028(4) = 53 and 53 = the 16th prime.
%t A126137 Table[np=NextPrime[E^n];pp=NextPrime[E^n,-1];If[E^n-pp<np-E^n,PrimePi[pp],PrimePi[np]],{n,0,31}] (* _James C. McMahon_, Dec 25 2024 *)
%Y A126137 Cf. A000720, A037028.
%K A126137 nonn
%O A126137 0,2
%A A126137 _Gary W. Adamson_, Dec 18 2006
%E A126137 Name edited by and more terms from _Jinyuan Wang_, Apr 10 2020
%E A126137 Offset corrected by _James C. McMahon_, Dec 25 2024