%I A061019
%S A061019 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,
%T A061019 27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,
%U A061019 50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70
%V A061019 1,-2,-3,4,-5,6,-7,-8,9,10,-11,-12,-13,14,15,16,-17,-18,-19,-20,21,22,
               -23,24,25,26,
%W A061019 -27,-28,-29,-30,-31,-32,33,34,35,36,-37,38,39,40,-41,-42,-43,-44,-45,
               46,-47,-48,49,
%X A061019 -50,51,-52,-53,54,55,56,57,58,-59,60,-61,62,-63,64,65,-66,-67,-68,69,
               -70
%N A061019 Negate primes in factorization of n.
%C A061019 Inverse Moebius transform of A001615.
%C A061019 n*lambda(n), where lambda is Liouville's function: A008836.
%C A061019 Totally multiplicative sequence with a(p) = -p for prime p. [From Jaroslav 
               Krizek (jaroslav.krizek(AT)atlas.cz), Nov 01 2009]
%F A061019 Multiplicative with a(p) = -p, p prime.
%F A061019 a(n)= (-1)^(number of primes dividing n)*n = n * (-1)^A001222(n).
%e A061019 a(6)=(-2)(-3) = +6, while a(8)=(-2)^3 = -8.
%Y A061019 Cf. A000027, A001222, A061020, A001615.
%Y A061019 Sequence in context: A105811 A069782 A088480 this_sequence A028310 A097045 
               A118759
%Y A061019 Adjacent sequences: A061016 A061017 A061018 this_sequence A061020 A061021 
               A061022
%K A061019 easy,nice,sign,mult
%O A061019 1,2
%A A061019 Marc LeBrun (mlb(AT)well.com), Apr 13 2001