A324696 Lexicographically earliest sequence containing 1 and all numbers divisible by prime(m) for some m not already in the sequence.
1, 3, 6, 7, 9, 11, 12, 14, 15, 18, 19, 21, 22, 24, 27, 28, 29, 30, 33, 35, 36, 38, 39, 41, 42, 44, 45, 48, 49, 51, 53, 54, 55, 56, 57, 58, 59, 60, 63, 66, 69, 70, 71, 72, 75, 76, 77, 78, 81, 82, 83, 84, 87, 88, 90, 91, 93, 95, 96, 97, 98, 99, 101, 102, 105
Offset: 1
Keywords
Examples
The sequence of terms together with their prime indices begins: 1: {} 3: {2} 6: {1,2} 7: {4} 9: {2,2} 11: {5} 12: {1,1,2} 14: {1,4} 15: {2,3} 18: {1,2,2} 19: {8} 21: {2,4} 22: {1,5} 24: {1,1,1,2} 27: {2,2,2} 28: {1,1,4} 29: {10} 30: {1,2,3} 33: {2,5} 35: {3,4} 36: {1,1,2,2}
Crossrefs
Programs
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Mathematica
aQ[n_]:=n==1||Or@@Cases[FactorInteger[n],{p_,k_}:>!aQ[PrimePi[p]]]; Select[Range[100],aQ]
Comments