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%I #14 Dec 02 2023 09:12:08
%S 10,15,20,22,26,30,33,34,35,38,39,40,44,45,46,50,51,52,57,58,60,62,66,
%T 68,69,70,74,75,76,77,78,80,82,86,87,88,90,91,92,93,94,99,100,102,104,
%U 105,106,110,111,114,116,117,118,119,120,122,123,124,129,130,132,133,134,135,136,138,140,141,142
%N Numbers k such that 1 < gcd(k, 42) < k and A007947(k) does not divide 42.
%C The asymptotic density of this sequence is 5/7. - _Amiram Eldar_, Dec 02 2023
%H Michael De Vlieger, <a href="/A362010/b362010.txt">Table of n, a(n) for n = 1..10000</a>
%H Michael De Vlieger, <a href="/A362010/a362010.png">Diagram showing numbers k in this sequence</a> instead as k mod 42, labeled and in large black circles, else gray dots if coprime to 42, purple if k = 1, red if k | 42, and gold if rad(k) | 42.
%F This sequence is { N \ { A108319 U A206547 } }.
%t With[{n = 42}, Select[Range[200], And[! CoprimeQ[#, n], ! Divisible[n, Times @@ FactorInteger[#][[All, 1]]]] & ] ]
%Y Cf. A007947, A108319, A206547.
%K nonn
%O 1,1
%A _Michael De Vlieger_, Apr 04 2023
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