OFFSET
0,5
LINKS
Antti Karttunen, Table of n, a(n) for n = 0..65537
FORMULA
a(n) = n - abs(mu(n))*n.
Sum_{k=1..n} a(k) ~ c * n^2, where c = (1 - 1/zeta(2))/2 = 0.1960364490... . - Amiram Eldar, Feb 22 2024
MATHEMATICA
Table[If[SquareFreeQ[n], 0, n], {n, 0, 100}] (* Harvey P. Dale, Aug 13 2016 *)
PROG
(PARI) A105570(n) = if(issquarefree(n), 0, n); \\ Antti Karttunen, Jul 03 2018
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Apr 14 2005
STATUS
approved