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 A353647 #14 May 07 2022 09:42:57
%S A353647 1,1,1,4,1,1,3,2,10,3,3,4,5,3,5,22,5,10,7,2,11,7,7,2,28,5,4,12,7,11,
%T A353647 15,6,11,11,11,40,17,7,17,10,11,11,19,8,6,15,15,22,32,26,17,26,17,4,
%U A353647 19,6,23,15,15,14,29,15,22,90,17,23,31,14,23,25,23,20,35,17,24,28,25,17,31,14,94,23,23,44,29,19
%N A353647 Möbius transform of A062401, where A062401(n) = phi(sigma(n)).
%C A353647 The first negative term is a(1944) = -76.
%H A353647 Antti Karttunen, <a href="/A353647/b353647.txt">Table of n, a(n) for n = 1..16384</a>
%F A353647 a(n) = Sum_{d|n} A008683(n/d) * A062401(d).
%t A353647 a[n_] := DivisorSum[n, MoebiusMu[n/#] * EulerPhi[DivisorSigma[1, #]] &]; Array[a, 100] (* _Amiram Eldar_, May 06 2022 *)
%o A353647 (PARI) A353647(n) = sumdiv(n,d,moebius(n/d)*eulerphi(sigma(d)));
%Y A353647 Cf. A000010, A000203, A008683, A062401.
%K A353647 sign
%O A353647 1,4
%A A353647 _Antti Karttunen_, May 06 2022