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 A119433 Primitive elements of A119432. 4
 2, 105, 165, 195, 3003, 3927, 4389, 4641, 4845, 5187, 5313, 5865, 6555, 7395, 7905, 8265, 8835, 9435, 10005, 10455, 10545, 10695, 10965, 11685, 11985, 12255, 12765, 13395, 13485, 13515, 14145, 14835, 15045, 15105, 15555, 16215, 16815, 17085 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Elements of A119432 that are not divisible by any smaller element of that sequence. Appears to be the lexicographically latest sequence of squarefree numbers such that all numbers with abundance >= -1 (see A103288) are divisible by one of the terms. - Peter Munn, Oct 19 2020 LINKS Charles R Greathouse IV, Table of n, a(n) for n = 1..10000 FORMULA 2 followed by odd elements of A119431. EXAMPLE From Peter Munn, Oct 23 2020: (Start) Initial terms, showing factorization:    n   a(n)    1      2 = 2    2    105 = 3 * 5 * 7    3    165 = 3 * 5 * 11    4    195 = 3 * 5 * 13    5   3003 = 3 * 7 * 11 * 13    6   3927 = 3 * 7 * 11 * 17    7   4389 = 3 * 7 * 11 * 19    8   4641 = 3 * 7 * 13 * 17    9   4845 = 3 * 5 * 17 * 19   10   5187 = 3 * 7 * 13 * 19   11   5313 = 3 * 7 * 11 * 23   12   5865 = 3 * 5 * 17 * 23   13   6555 = 3 * 5 * 19 * 23   14   7395 = 3 * 5 * 17 * 29   15   7905 = 3 * 5 * 17 * 31 (End) MATHEMATICA Block[{a = {}}, Do[If[And[NoneTrue[a, Mod[i, #] == 0 &], 2 EulerPhi[i] <= i], AppendTo[a, i]], {i, 20000}]; a] (* Michael De Vlieger, Nov 05 2020 *) CROSSREFS Subsequence of A005117, A119432. Cf. A103288. Sequence in context: A265655 A001184 A098653 * A307227 A042351 A258828 Adjacent sequences:  A119430 A119431 A119432 * A119434 A119435 A119436 KEYWORD nonn AUTHOR Franklin T. Adams-Watters, May 19 2006 STATUS approved

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Last modified May 6 16:03 EDT 2021. Contains 343586 sequences. (Running on oeis4.)