OFFSET
1,1
COMMENTS
This sequence is a subsequence of A100306, Numbers for which the values of the Moebius function and the Mertens function agree.
LINKS
Donovan Johnson, Table of n, a(n) for n = 1..10000
PrimeFan, Esoteric Integer Sequences
EXAMPLE
102 is in the sequence because it is a sphenic number (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.
MATHEMATICA
(* If not already defined *) If[Names["Mertens"] == {}, Mertens[x_] := Plus @@ MoebiusMu[Range[1, x]]]; Select[Range[2500], MoebiusMu[ # ] == -1 && Mertens[ # ] == -1 &]
CROSSREFS
KEYWORD
nonn
AUTHOR
Alonso del Arte, Jan 03 2005
EXTENSIONS
Offset corrected by Donovan Johnson, Jun 19 2012
STATUS
approved