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 A333449 #9 Mar 22 2020 04:01:38
%S A333449 2,5,9,14,20,27,33,40,48,61,65,80,86,95,107,120,128,141,149,168,178,
%T A333449 189,195,218,232,243,253,268,272,297,313,330,342,353,373,396,404,419,
%U A333449 431,458,466,483,495,510,530,539,553,594,604,627,641,660,664,689,703,726,742,749,757,798
%N A333449 a(n) = Sum_{k=1..n} prime(floor(n/k)).
%F A333449 G.f.: (1/(1 - x)) * (2*x/(1 - x) + Sum_{k>=2} (prime(k) - prime(k-1))*x^k/(1 - x^k)).
%F A333449 Sum_{k=1..n} mu(k) * a(floor(n/k)) = prime(n).
%t A333449 Table[Sum[Prime[Floor[n/k]], {k, 1, n}], {n, 1, 60}]
%t A333449 g[1] = 2; g[n_] := Prime[n] - Prime[n - 1]; a[n_] := Sum[Sum[g[d], {d, Divisors[k]}], {k, 1, n}]; Table[a[n], {n, 1, 60}]
%o A333449 (PARI) a(n) = sum(k=1, n, prime(n\k)); \\ _Michel Marcus_, Mar 22 2020
%Y A333449 Cf. A000040, A001223, A007445, A007504, A008683, A333450.
%K A333449 nonn
%O A333449 1,1
%A A333449 _Ilya Gutkovskiy_, Mar 21 2020