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 A073644 Largest k such that the harmonic mean of phi(n), phi(n+1), ...., phi(n+x) is an integer for any x with 0<=x<=k. 0

%I

%S 1,0,1,0,0,1,0,0,0,0,0,2,3,0,1,0,0,1,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,

%T 1,2,2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,0,0,

%U 0,0,0,2,2,0,0,1,0,0,0,0,0,0,0,0,0,2,0,1,0,1,0,0,0,0,0,1,0,0,1,0,0,0,0,1,0

%N Largest k such that the harmonic mean of phi(n), phi(n+1), ...., phi(n+x) is an integer for any x with 0<=x<=k.

%C Largest k such that (x+1)/sum(i=0,x,1/phi(n+i)) is an integer for 0<=x<=k. It seems that a(n)<=5.

%K easy,nonn

%O 1,12

%A _Benoit Cloitre_, Sep 01 2002

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Last modified December 11 12:33 EST 2019. Contains 329916 sequences. (Running on oeis4.)