login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A076545 sum[k=1 to n] mu(k)+sqf(k): mu(k) is Moebius function; sqf(k)=1 if k is squarefree, sqf(k)=-1 otherwise. 0

%I #8 Jun 02 2022 20:39:03

%S 2,2,2,1,1,3,3,2,1,3,3,2,2,4,6,5,5,4,4,3,5,7,7,6,5,7,6,5,5,5,5,4,6,8,

%T 10,9,9,11,13,12,12,12,12,11,10,12,12,11,10,9,11,10,10,9,11,10,12,14,

%U 14,13,13,15,14,13,15,15,15,14,16,16,16,15,15,17,16,15,17,17,17,16,15

%N sum[k=1 to n] mu(k)+sqf(k): mu(k) is Moebius function; sqf(k)=1 if k is squarefree, sqf(k)=-1 otherwise.

%t Accumulate[Table[MoebiusMu[n]+If[SquareFreeQ[n],1,-1],{n,100}]] (* _Harvey P. Dale_, Jun 02 2022 *)

%K easy,nonn

%O 1,1

%A _Zak Seidov_, Oct 19 2002

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 28 09:04 EDT 2024. Contains 371240 sequences. (Running on oeis4.)