OFFSET
1,2
EXAMPLE
a(6) = 1^mu(1)+2^mu(2)+3^mu(3)+4^mu(4)+5^mu(5)+6^mu(6) = 1^1+2^(-1)+3^(-1)+4^0+5^(-1)+6^1 = 1 + 1/2 + 1/3 + 1 + 1/5 + 6 = (30+15+10+30+6+180)/30 = 271/30, therefore a(6)=271, A080326(6)=30.
MATHEMATICA
Accumulate[Table[n^MoebiusMu[n], {n, 30}]]//Numerator (* Harvey P. Dale, Nov 13 2021 *)
PROG
(PARI) a(n) = numerator(sum(k = 1, n, k^moebius(k))); \\ Michel Marcus, Aug 29 2013
CROSSREFS
KEYWORD
nonn,frac
AUTHOR
Reinhard Zumkeller, Feb 13 2003
STATUS
approved