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 A174112 #11 Oct 26 2015 23:00:16
%S A174112 1,2,4,5,9,9,15,16,21,23,33,29,41,45,51,52,68,65,83,81,91,99,121,109,
%T A174112 128,138,152,152,180,168,198,199,217,231,253,234,270,286,308,298,338,
%U A174112 326,368
%N A174112 After correction, duplicate of A111490.
%F A174112 a(n) = Sum_{i=1..n} A033879(i) = Sum_{i=1..n} (2*i - (sum of divisors of i)) = Sum_{i=1..n} (A005843(i)-A000203(i) = Sum_{i=1..n}(A005843(i) - Sum{i=1..n} A000203(i).
%K A174112 dead
%O A174112 1,2