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 A080326 #10 Jul 28 2021 18:53:38
%S A080326 1,2,6,6,30,30,210,210,210,210,2310,2310,30030,30030,30030,30030,
%T A080326 510510,510510,9699690,9699690,9699690,9699690,223092870,223092870,
%U A080326 223092870,223092870,223092870,223092870,6469693230,3234846615
%N A080326 Denominator of Sum(k^mu(k): 1<=k<=n), where mu is the Moebius function (A008683).
%C A080326 a(n) is a divisor of A034386(n), the product of the primes <= n. Does a(n) = A034386(n) for infinitely many n?
%H A080326 Harvey P. Dale, <a href="/A080326/b080326.txt">Table of n, a(n) for n = 1..1000</a>
%t A080326 Accumulate[Table[n^MoebiusMu[n],{n,30}]]//Denominator (* _Harvey P. Dale_, Jul 28 2021 *)
%o A080326 (PARI) a(n) = denominator(sum(k = 1, n, k^moebius(k))); \\ _Michel Marcus_, Aug 29 2013
%Y A080326 Numerators are in A080306. Cf. A080304, A080305, A034386.
%K A080326 nonn,frac
%O A080326 1,2
%A A080326 _Dean Hickerson_, Feb 15 2003