%I A028415
%S A028415 1,2,5,3,13,15,47,25,13,55,281,74,301,311,637,163,1319,453,4117,4207,4267,
%T A028415 4339,48089,49079,9895,10027,10115,10247,72125,73511,369403,93217,9391,
%U A028415 75821,76283,77207,77515,78131,78593,39643,49727,100609,100939,25408,204419
%N A028415 Numerator of Sum_{k=1..n} 1/phi(k).
%D A028415 D. S. Mitrinovic et al., Handbook of Number Theory, Kluwer, Section I.27.
%H A028415 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               TotientSummatoryFunction.html">Totient Summatory Function</a>
%e A028415 1, 2, 5/2, 3, 13/4, 15/4, 47/12, 25/6, 13/3, 55/12, 281/60, 74/15, ...
%Y A028415 Cf. A048049.
%Y A028415 Sequence in context: A120858 A124937 A091265 this_sequence A035334 A002565 
               A063703
%Y A028415 Adjacent sequences: A028412 A028413 A028414 this_sequence A028416 A028417 
               A028418
%K A028415 nonn,frac
%O A028415 1,2
%A A028415 N. J. A. Sloane (njas(AT)research.att.com), Jun 28 2002