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 A069914 #13 Aug 20 2021 00:21:31
%S A069914 0,1,2,6,4,15,6,23,16,27,10,64,12,39,42,72,16,98,18,110,60,63,22,213,
%T A069914 48,75,84,156,28,245,30,201,96,99,102,380,36,111,114,357,40,345,42,
%U A069914 248,248,135,46,618,96,278,150,294,52,478,162,501,168,171,58,924,60,183
%N A069914 a(n) = Sum_{d|n} (d-1)*sigma(n/d).
%H A069914 Ivan Neretin, <a href="/A069914/b069914.txt">Table of n, a(n) for n = 1..10000</a>
%F A069914 a(n) = A060640(n) - A007429(n).
%F A069914 G.f.: Sum_{k>=1} sigma(k) * x^(2*k) / (1 - x^k)^2. - _Ilya Gutkovskiy_, Aug 19 2021
%t A069914 Table[Plus @@ (DivisorSigma[1, ds = Divisors[n]]*(n/ds - 1)), {n, 62}] (* _Ivan Neretin_, May 17 2015 *)
%o A069914 (PARI) a(n) = sumdiv(n, d, (d-1)*sigma(n/d)) \\ _Michel Marcus_, Jun 17 2013
%Y A069914 Cf. A000203, A006579, A007429, A060640.
%K A069914 nonn
%O A069914 1,3
%A A069914 _Vladeta Jovovic_, May 04 2002