%I A048864
%S A048864 1,1,1,1,2,1,3,1,3,2,6,1,7,2,4,3,10,1,11,2,6,4,14,1,12,5,10,5,19,1,20,
%T A048864 6,11,7,15,3,25,8,14,6,28,2,29,8,12,10,32,3,28,7,19,11,37,4,26,10,22,
%U A048864 14,42,2,43,14,20,15,32,5,48,15,27,8,51,6,52,17,21,17,41,6,57,12,33,20
%N A048864 Number of nonprime numbers (composites and 1) in the reduced residue
system of n.
%C A048864 Differs from A039776 at n = 20, 21, ...
%F A048864 A000010(n) -[ A000720(n)-A(001221) ]
%e A048864 at n=100 Phi(100) = 40 Phi(100)-[ Pi(100)-A001221(100) ]=17, thus a(100)
= 17
%Y A048864 Cf. A039776, A000010, A000720, A001221.
%Y A048864 Sequence in context: A046073 A162912 A039776 this_sequence A003139 A145652
A111248
%Y A048864 Adjacent sequences: A048861 A048862 A048863 this_sequence A048865 A048866
A048867
%K A048864 nonn
%O A048864 1,5
%A A048864 Labos E. (labos(AT)ana.sote.hu)
|