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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A100765 Numbers for which the values of the Moebius function (A008683) and the Mertens function (A002321) are both -1. 5

%I

%S 3,41,59,66,102,151,165,167,233,239,255,354,357,359,367,402,406,409,

%T 421,426,429,609,638,782,786,797,826,854,885,887,890,894,897,907,911,

%U 1015,1019,1221,1259,1281,1283,1298,1301,1303,1307,1319,1327,1493,1526,1533

%N Numbers for which the values of the Moebius function (A008683) and the Mertens function (A002321) are both -1.

%C This sequence is a subsequence of A100306, Numbers for which the values of the Moebius function and the Mertens function agree.

%H Donovan Johnson, <a href="/A100765/b100765.txt">Table of n, a(n) for n = 1..10000</a>

%H PrimeFan, <a href="http://primefan.tripod.com/EsotericIntegerSequences.html">Esoteric Integer Sequences</a>

%e 102 is in the sequence because it is a sphenic (exactly 3 distinct prime factors, A007304) number, so the Mobius function yields -1 and the sum of that value and the previous Mobius values (the Mertens function) is also -1.

%t (* If not already defined *) If[Names["Mertens"] == {}, Mertens[x_] := Plus @@ MoebiusMu[Range[1, x]]]; Select[Range[2500], MoebiusMu[ # ] == -1 && Mertens[ # ] == -1 &]

%Y Cf. A100306, A100766, A100767.

%K nonn,changed

%O 1,1

%A _Alonso del Arte_, Jan 03 2005

%E Offset corrected by _Donovan Johnson_, Jun 19 2012

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.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 17 21:11 EDT 2021. Contains 343990 sequences. (Running on oeis4.)