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!)
A098991 Numbers n where A098035(n)=0. 1
5, 9, 13, 15, 21, 27, 33, 35, 37, 39, 50, 55, 57, 61, 65, 73, 91, 93, 95, 111, 114, 115, 121, 122, 133, 141, 143, 145, 147, 155, 157, 170, 177, 183, 185, 189, 193, 195, 201, 205, 209, 213, 215, 217, 219, 231, 235, 247, 253, 259, 261, 277, 285, 295, 299, 301, 313 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Indranil Ghosh, Table of n, a(n) for n = 1..935 (terms < 5000)
FORMULA
Sum_{k|n} mu(k+1), where mu() is Moebius function.
MATHEMATICA
f[n_] := Plus @@ MoebiusMu[Divisors[n] + 1]; Select[ Range[319], f[ # ] == 0 &]
PROG
(PARI) a(n) = sumdiv(n, k, moebius(k + 1));
for(n=1, 320, if(a(n) == 0, print1(n, ", "))) \\ Indranil Ghosh, Mar 16 2017
CROSSREFS
Cf. A098035.
Sequence in context: A314654 A314655 A314656 * A314657 A314658 A116616
KEYWORD
nonn
AUTHOR
STATUS
approved

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 April 19 16:52 EDT 2024. Contains 371794 sequences. (Running on oeis4.)