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 A232533 #27 Mar 04 2018 09:38:48
%S A232533 1,3,7,13,24,35,57,79,110,142,198,237,316,381,455,541,678,770,942,
%T A232533 1058,1209,1376,1630,1781,2042,2278,2552,2789,3196,3417,3883,4225,
%U A232533 4614,5024,5476,5812,6479,6994,7544,7996,8817,9269,10173,10784,11425,12186,13268
%N A232533 a(n) = Sum_{i=1...n} Sum_{j=1..i} lcm(i,j)/i.
%C A232533 Partial sums of A057661.
%H A232533 Project Euler, <a href="http://projecteuler.net/problem=448">Problem 448: Average least common multiple</a>
%e A232533 a(3) = lcm(1,1)/1 + (lcm(2,1) + lcm(2,2))/2 + (lcm(3,1) + lcm(3,2) + lcm(3,3))/3 = 7.
%t A232533 Table[Sum[Sum[LCM[m, k], {k, m}]/m, {m, n}], {n, 50}] (* _T. D. Noe_, Nov 25 2013 *)
%o A232533 (PARI) a(n)=sum(k=1,n,sum(b=1,k,lcm(b,k)/k));
%o A232533 (PARI) a(n)=sum(k=1,n,sum(m=1,k,m/gcd(m,k))); \\ _Charles R Greathouse IV_, Nov 25 2013
%Y A232533 Cf. A057661.
%K A232533 nonn
%O A232533 1,2
%A A232533 _Zhining Yang_, Nov 25 2013