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 A069637 Number of prime powers <= n with exponents >1. 6

%I

%S 0,0,0,1,1,1,1,2,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,4,5,5,6,6,6,6,6,7,7,7,

%T 7,7,7,7,7,7,7,7,7,7,7,7,7,7,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,9,9,9,9,9,

%U 9,9,9,9,9,9,9,9,9,9,9,9,10,10,10,10,10,10,10,10,10,10,10,10,10,10

%N Number of prime powers <= n with exponents >1.

%C Counts A025475 without 1=prime^0: a(n)=A085501(n)-1. - _Reinhard Zumkeller_, Jul 03 2003

%H Daniel Forgues, <a href="/A069637/b069637.txt">Table of n, a(n) for n=1,...,100000</a>.

%F a(n) = A025528(n) - A000720(n) = A000720([n^(1/2)]) + A000720([n^(1/3)]) + ... . - _Max Alekseyev_, May 11 2009

%K nonn

%O 1,8

%A _Amarnath Murthy_, Mar 27 2002

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Last modified September 22 13:05 EDT 2019. Contains 327307 sequences. (Running on oeis4.)