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 A335138 #27 Jul 22 2020 13:23:05
%S A335138 3,5,5,5,6,7,9,10,7,11,8,13,8,15,12,11,10,11,11,13,13,14,13,14,13,15,
%T A335138 14,15,13,19,17,17,17,19,16,19,15,14,17,17,15,22,17,23,20,19,17,19,17,
%U A335138 19,19,21,19,21,19,21,21,21,21,23,22,22,22,19,21,23,23,23
%N A335138 a(n) = 1 + Sum_{k=1..2*n} sign((sign(n+Sum_{j=2..k}-|A309229(n,j)|)+1)).
%C A335138 a(n) appears to be asymptotic to sqrt(8*n). Taken from the comment by Lekraj Beedassy in A003418: "An assertion equivalent to the Riemann hypothesis is:
%C A335138 | Sum_{k>=1} (A309229(n, k)/k - 1/k) - n | < sqrt(n) * log(n)^2."
%F A335138 a(n) = 1 + Sum_{k=1..2*n} sign((sign(n+Sum_{j=2..k}-|A309229(n,j)|)+1)).
%t A335138 nn = 68; f[n_] := n; h[n_] := DivisorSum[n, MoebiusMu[#] # &]; A = Accumulate[Table[Table[h[GCD[n, k]], {k, 1, nn}], {n, 1, nn}]]; B = -Abs[A]; B[[All, 1]] = Table[f[n], {n, 1, nn}]; b = 1 + Total[Sign[1 + Sign[Accumulate[Transpose[B]]]]]
%Y A335138 Cf. A309229.
%K A335138 nonn
%O A335138 1,1
%A A335138 _Mats Granvik_, Jun 09 2020