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Complement of A036668: numbers not of the form 2^i*3^j*k, i + j even, (k,6) = 1.
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%I #25 Sep 20 2020 08:21:57

%S 2,3,8,10,12,14,15,18,21,22,26,27,32,33,34,38,39,40,46,48,50,51,56,57,

%T 58,60,62,69,70,72,74,75,82,84,86,87,88,90,93,94,98,104,105,106,108,

%U 110,111,118,122,123,126,128,129,130,132,134,135,136,141,142

%N Complement of A036668: numbers not of the form 2^i*3^j*k, i + j even, (k,6) = 1.

%C These are the numbers 2x and 3x as x ranges through the numbers in A036668.

%C Numbers whose squarefree part is divisible by exactly one of {2, 3}. - _Peter Munn_, Aug 24 2020

%C The asymptotic density of this sequence is 5/12. - _Amiram Eldar_, Sep 20 2020

%H Clark Kimberling, <a href="/A325424/b325424.txt">Table of n, a(n) for n = 1..10000</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/SymmetricDifference.html">Symmetric difference</a>

%F (2 * {A036668}) union (3 * {A036668}). - _Sean A. Irvine_, May 19 2019

%t a = {1}; Do[AppendTo[a, NestWhile[# + 1 &, Last[a] + 1, Apply[Or,

%t Map[MemberQ[a, #] &, Select[Flatten[{#/3, #/2}],

%t IntegerQ]]] &]], {150}]; a (* A036668 *)

%t Complement[Range[Last[a]], a] (* A325424 *)

%t (* _Peter J. C. Moses_, Apr 23 2019 *)

%Y Cf. A325417, A036668.

%Y Symmetric difference of: A003159 and A007417; A036554 and A145204\{0}.

%K nonn,easy

%O 1,1

%A _Clark Kimberling_, Apr 26 2019