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 A332654 #12 Sep 08 2022 08:46:25 %S A332654 1,2,6,12,31,33,92,96,165,172,386,239,651,499,656,776,1497,846,2110, %T A332654 1262,1903,2037,3796,1867,4181,3408,4530,3673,7715,3183,9456,6232, %U A332654 7761,7754,10062,6248,16207,10889,12980,9906,22141,9308,25586,15027,17075,19483,33512,14851 %N A332654 a(n) = Sum_{k=1..n} (k/gcd(n, k))^2. %C A332654 Inverse Moebius transform of A053818. %H A332654 Seiichi Manyama, <a href="/A332654/b332654.txt">Table of n, a(n) for n = 1..10000</a> %F A332654 a(n) = Sum_{k=1..n} (lcm(n, k)/n)^2. %F A332654 a(n) = Sum_{d|n} Sum_{k=1..d, gcd(k, d) = 1} k^2. %t A332654 Table[Sum[(k/GCD[n, k])^2, {k, 1, n}], {n, 1, 48}] %t A332654 Table[Sum[Sum[If[GCD[k, d] == 1, k^2, 0], {k, 1, d}], {d, Divisors[n]}], {n, 1, 48}] %o A332654 (Magma) [&+[(k div Gcd(n,k))^2:k in [1..n]]:n in [1..50]]; // _Marius A. Burtea_, Feb 18 2020 %Y A332654 Cf. A053818, A057661, A068963, A069097, A320941, A332655. %K A332654 nonn %O A332654 1,2 %A A332654 _Ilya Gutkovskiy_, Feb 18 2020