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%I #13 Dec 15 2017 17:35:09
%S 1,1,1,2,1,2,1,2,2,2,1,3,1,2,3,3,1,3,1,3,3,2,1,4,2,2,3,3,1,4,1,3,3,2,
%T 3,4,1,2,3,4,1,4,1,3,4,2,1,5,2,3,3,3,1,4,3,4,3,2,1,6,1,2,4,4,3,4,1,3,
%U 3,5,1,5,1,2,4,3,3,4,1,5,3,2,1,6,3,2,3,4,1,6,3,3,3,2,3,5,1,4,4,5,1,4,1,4,5
%N a(n) = floor of Sum_{ d divides n } phi(d)/d.
%D D. M. Burton, Elementary Number Theory, Allyn and Bacon Inc. Boston, MA, 1976, p. 152.
%H Harry J. Smith, <a href="/A062362/b062362.txt">Table of n, a(n) for n=1,...,1000</a>
%p A062362 := proc(n) add(numtheory[phi](d)/d,d=numtheory[divisors](n)) ; floor(%) ; end: # _R. J. Mathar_, Jun 28 2009
%o (PARI) j=[]; for(n=1,250,j=concat(j,floor(sumdiv(n,d,eulerphi(d)/d)))); j
%o (PARI) { for (n=1, 1000, write("b062362.txt", n, " ", floor(sumdiv(n, d, eulerphi(d)/d))) ) } \\ _Harry J. Smith_, Aug 06 2009
%K easy,nonn
%O 1,4
%A _Jason Earls_, Jul 07 2001
%E Definition clarified by _R. J. Mathar_, Jun 28 2009
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