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

60, 140, 210, 315, 462, 504, 616, 693, 728, 770, 792, 819, 910, 936, 990, 1001, 1092, 1144, 1170, 1287, 1430, 1530, 1683, 1716, 1870, 1989, 2090, 2142, 2145, 2210, 2244, 2431, 2448, 2470, 2508, 2618, 2652, 2717, 2805, 2926, 2964, 2992, 3094, 3135, 3230, 3315

Offset: 1

Author

Amiram Eldar, Jul 21 2020

Keywords

• nonn

Comments

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

Examples

			60 is a term since it is a term of A336442 but none of its proper divisors are in A336442.
120 is not a term: although it is in A336442, it is a multiple of 60 which is also a term of A336442.
		

Links

• David A. Corneth, Table of n, a(n) for n = 1..10347

Crossrefs

Analogous to A302022 as A336442 is analogous to A005279.

Programs

Mathematica

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]