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%I A050320
%S A050320 1,1,1,1,1,2,1,1,1,2,1,2,1,2,2,1,1,2,1,2,2,2,1,2,1,2,1,2,1,5,1,1,2,2,2,
%T A050320 3,1,2,2,2,1,5,1,2,2,2,1,2,1,2,2,2,1,2,2,2,2,2,1,6,1,2,2,1,2,5,1,2,2,
%U A050320 5,1,3,1,2,2,2,2,5,1,2,1,2,1,6,2,2,2,2,1,6,2,2,2,2,2,2,1,2,2,3,1,5,1
%N A050320 Number of ways n is a product of square-free numbers > 1.
%C A050320 a(n) depends only on prime signature of n (cf. A025487). So a(24) = a(375) 
               since 24=2^3*3 and 375=3*5^3 both have prime signature (3,1).
%F A050320 Dirichlet g.f.: prod{n is square-free and > 1}(1/(1-1/n^s)).
%Y A050320 Cf. A001055, A005117, A050325. a(p^k)=1. a(A002110)=A000110.
%Y A050320 a(n!)=A103774(n).
%Y A050320 Sequence in context: A064372 A096825 A007875 this_sequence A121382 A051265 
               A008647
%Y A050320 Adjacent sequences: A050317 A050318 A050319 this_sequence A050321 A050322 
               A050323
%K A050320 nonn,easy,nice
%O A050320 1,6
%A A050320 Christian G. Bower (bowerc(AT)usa.net), Sep 15 1999.

    
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Last modified December 21 10:15 EST 2009. Contains 171081 sequences.


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