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A235495 Numbers n such that pi(2n) divides n. 1

%I

%S 1,2,3,4,48,50,60,504,540,546,558,561,564,567,4204,4212,4220,4228,

%T 4232,4236,32270,32290,32305,32310,32325,32345,32350,32355,32360,

%U 240426,240432,240504,240510,240516,240522,240528,240534,240540,240546,240648,240678,240684

%N Numbers n such that pi(2n) divides n.

%H Vincenzo Librandi, <a href="/A235495/b235495.txt">Table of n, a(n) for n = 1..59</a>

%e 48 is in the sequence because pi(2*48) = 24 and 24 divides 48.

%t Select[Range[10^6],IntegerQ[#/PrimePi[2#]]&]

%o (PARI) is(n)=n%primepi(2*n)==0 \\ _Charles R Greathouse IV_, Jan 12 2014

%Y Cf. A057809.

%K nonn

%O 1,2

%A _Vincenzo Librandi_, Jan 11 2014

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Last modified September 26 02:27 EDT 2021. Contains 347664 sequences. (Running on oeis4.)