A119433 Primitive elements of A119432.
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
Offset: 1
Keywords
Examples
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)
Links
- Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
Programs
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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 *)
Formula
2 followed by odd elements of A119431.
Comments