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A336443 Primitive terms of A336442: terms k of A336442 such that none of the proper divisors of k are in A336442. 3

%I

%S 60,140,210,315,462,504,616,693,728,770,792,819,910,936,990,1001,1092,

%T 1144,1170,1287,1430,1530,1683,1716,1870,1989,2090,2142,2145,2210,

%U 2244,2431,2448,2470,2508,2618,2652,2717,2805,2926,2964,2992,3094,3135,3230,3315

%N Primitive terms of A336442: terms k of A336442 such that none of the proper divisors of k are in A336442.

%C Any term of A336442 is a multiple of at least one term of this sequence.

%H David A. Corneth, <a href="/A336443/b336443.txt">Table of n, a(n) for n = 1..10347</a>

%e 60 is a term since it is a term of A336442 but none of its proper divisors are in A336442.

%e 120 is not a term: although it is in A336442, it is a multiple of 60 which is also a term of A336442.

%t divQ[n_] := AnyTrue[Subsets[Divisors[n], {3}], And @@ CoprimeQ @@@ Subsets[#, {2}] && #[[3]] < 2 #[[1]] &]; primQ[n_] := divQ[n] && AllTrue[Most[Divisors[n]], ! divQ[#] &]; Select[Range[3333], primQ]

%Y Analogous to A302022 as A336442 is analogous to A005279.

%K nonn

%O 1,1

%A _Amiram Eldar_, Jul 21 2020

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Last modified May 18 23:31 EDT 2022. Contains 353826 sequences. (Running on oeis4.)