%I A072165
%S A072165 0,1,0,1,1,1,1,1,0,1,1,1,1,1,1,1,0,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
%T A072165 1,1,1,1,0,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
%U A072165 1,1,1,1,1,1,1,1
%N A072165 Values of Moebius function of the products of two (not necessarily distinct) 
               primes (semiprimes or 2-almost primes, A001358).
%H A072165 Kimberly Schneider, <a href="http://planetmath.org/?op=getobj&from=objects&name=MoebiusFunction">
               Moebius function.</a>
%p A072165 semiprimes := proc(d_n) local a,i; a := [ ]; for i from 1 to d_n do if((tau(i) 
               = 3) or ((mobius(i) <> 0) and (tau(i) = 4))) then a := [ op(a), mobius(i) 
               ]; fi; od: RETURN(a); end;
%Y A072165 Sequence in context: A023532 A112690 A115971 this_sequence A072608 A125720 
               A095130
%Y A072165 Adjacent sequences: A072162 A072163 A072164 this_sequence A072166 A072167 
               A072168
%K A072165 easy,nonn
%O A072165 1,1
%A A072165 Jani Melik (jani_melik(AT)hotmail.com), Jun 28 2002