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 A331376 #11 Feb 05 2024 17:04:08
%S A331376 1,2,4,5,8,8,12,8,16,16,20,16,24,24,24,16,32,32,36,32,36,40,44,24,56,
%T A331376 48,60,48,56,48,60,32,60,64,72,60,72,72,72,48,80,72,84,80,88,88,92,44,
%U A331376 120,112,96,96,104,120,120
%N A331376 Dirichlet convolution of the reduced totient function with itself.
%C A331376 Differs from A029935 when A002322 differs from A000010.
%F A331376 a(n) = Sum{d|n} A002322(d) * A002322(n/d).
%o A331376 (PARI) a(n) = sumdiv(n, d, lcm(znstar(d)[2]) * lcm(znstar(n/d)[2]));
%Y A331376 Cf. A000010, A029935, A002322.
%K A331376 nonn
%O A331376 1,2
%A A331376 _Torlach Rush_, Jan 14 2020