A364614 Numbers not divisible by any prime of the form 3*k - 1.
1, 3, 7, 9, 13, 19, 21, 27, 31, 37, 39, 43, 49, 57, 61, 63, 67, 73, 79, 81, 91, 93, 97, 103, 109, 111, 117, 127, 129, 133, 139, 147, 151, 157, 163, 169, 171, 181, 183, 189, 193, 199, 201, 211, 217, 219, 223, 229, 237, 241, 243, 247, 259, 271, 273, 277, 279
Offset: 1
Keywords
Programs
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Mathematica
s = Select[Prime[Range[100]], Mod[#, 3] == 2 &] (* A003627 *) Select[r = Range[Max[s]], Intersection[#/s, r] == {} &]
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