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 A136177 Number of exponents in the prime-factorization of n that are coprime to n. 2

%I

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

%T 2,0,1,2,2,2,1,3,1,1,2,2,1,1,1,1,2,1,1,1,2,2,2,2,1,2,1,2,2,0,2,3,1,1,

%U 2,3,1,0,1,2,2,1,2,3,1,1,1,2,1,2,2,2,2,2,1,2,2,1,2,2,2,2,1,1,2,0,1,3,1,2,3

%N Number of exponents in the prime-factorization of n that are coprime to n.

%e 8000 = 2^6 * 5^3. 6 is not coprime to 8000, but 3 is. So a(8000) = 1.

%t Table[Length[Select[Table[FactorInteger[n][[i, 2]], {i, 1, Length[FactorInteger[n]]}], GCD[ #, n] == 1 &]], {n, 2, 90}] - _Stefan Steinerberger_, Dec 21 2007

%o (PARI) A136177(n)={local(t);sum(j=1,#t=factor(n)[,2]~,gcd(n,t[j])==1)} \\ - M. F. Hasler, Dec 21 2007

%Y Cf. A136176.

%K nonn,easy

%O 1,6

%A Leroy Quet, Dec 19 2007

%E More terms from _M. F. Hasler_ and _Stefan Steinerberger_, Dec 21 2007

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