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 A349124 #11 Nov 15 2021 03:40:22 %S A349124 0,1,1,4,1,15,1,10,4,21,1,48,1,27,24,20,1,42,1,72,30,39,1,110,4,45,10, %T A349124 96,1,279,1,35,42,57,36,120,1,63,48,170,1,369,1,144,78,75,1,210,4,54, %U A349124 60,168,1,90,48,230,66,93,1,828,1,99,102,56,54,549,1,216,78,531,1,260,1,117,66,240,54,639,1,330,20,129 %N A349124 a(n) = A349123(n) / A003557(n), where A349123 is the Dirichlet convolution of the arithmetic derivative with n*tau(n). %H A349124 Antti Karttunen, <a href="/A349124/b349124.txt">Table of n, a(n) for n = 1..16384</a> %F A349124 a(n) = A349123(n) / A003557(n). %t A349124 f[p_, e_] := p^(e - 1); s[1] = 1; s[n_] := Times @@ f @@@ FactorInteger[n]; d[1] = 0; d[n_] := n*Plus @@ ((Last[#]/First[#]) & /@ FactorInteger[n]); a[n_] := DivisorSum[n, d[#]*(n/#)*DivisorSigma[0, n/#] &] / s[n]; Array[a, 100] (* _Amiram Eldar_, Nov 08 2021 *) %o A349124 (PARI) %o A349124 A003557(n) = (n/factorback(factorint(n)[, 1])); %o A349124 A349124(n) = (A349123(n) / A003557(n)); \\ Needs also code from A349123. %Y A349124 Cf. A003415, A003557, A038040, A349123. %Y A349124 Cf. also A347129. %K A349124 nonn %O A349124 1,4 %A A349124 _Antti Karttunen_, Nov 08 2021