The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A103449 Values of k such that Sum_{m=0..k} Moebius(binomial(k,m)) = 0. 3
 3, 12, 24, 29, 34, 40, 54, 60, 67, 68, 75, 86, 93, 97, 102, 119, 125, 131, 133, 142, 152, 157, 160, 163, 164, 168, 170, 172, 189, 193, 197, 208, 210, 220, 221, 228, 229, 246, 251, 255, 257, 261, 270, 275, 280, 293, 296, 307, 308, 313, 315, 332, 337, 338, 340 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Values of k such that A103448(k) = 0. LINKS G. C. Greubel, Table of n, a(n) for n = 1..1000 EXAMPLE 12 belongs to the sequence because the only squarefree values of binomial(12,m) are 1, 2*3*11, 2*3*11, 1, on which the Mobius function takes the values 1,-1,-1,1, respectively. 8 does not belong to the sequence because the only squarefree value of binomial(8,m) are 1, 2*5*7, 1, on which the Moebius function takes the values 1,-1,1, respectively. MATHEMATICA A103448[n_]:= A103448[n]= Sum[MoebiusMu[Binomial[n, k]], {k, 0, n}]; f:= Table[A103448[n], {n, 0, 1050}]; Select[Range[0, 1000], f[[#]] == 0 &] - 1  (* G. C. Greubel, Jun 17 2021 *) PROG (PARI) is(k) = sum(m=0, k, moebius(binomial(k, m)))==0 \\ Felix Fröhlich, Jun 18 2021 CROSSREFS Cf. A008683, A103447, A103448. Sequence in context: A332349 A242636 A012469 * A030571 A297675 A112236 Adjacent sequences:  A103446 A103447 A103448 * A103450 A103451 A103452 KEYWORD nonn AUTHOR Emeric Deutsch, Feb 07 2005 STATUS approved

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

Last modified July 26 01:33 EDT 2021. Contains 346294 sequences. (Running on oeis4.)