A336620 Numbers that are not a product of elements of A304711.
3, 5, 7, 9, 11, 13, 17, 19, 21, 23, 25, 27, 29, 31, 37, 39, 41, 42, 43, 47, 49, 53, 57, 59, 61, 63, 65, 67, 71, 73, 78, 79, 81, 83, 87, 89, 91, 97, 101, 103, 105, 107, 109, 111, 113, 114, 115, 117, 121, 125, 126, 127, 129, 130, 131, 133, 137, 139, 147, 149
Offset: 1
Keywords
Examples
The sequence of terms together with their prime indices begins: 3: {2} 39: {2,6} 78: {1,2,6} 5: {3} 41: {13} 79: {22} 7: {4} 42: {1,2,4} 81: {2,2,2,2} 9: {2,2} 43: {14} 83: {23} 11: {5} 47: {15} 87: {2,10} 13: {6} 49: {4,4} 89: {24} 17: {7} 53: {16} 91: {4,6} 19: {8} 57: {2,8} 97: {25} 21: {2,4} 59: {17} 101: {26} 23: {9} 61: {18} 103: {27} 25: {3,3} 63: {2,2,4} 105: {2,3,4} 27: {2,2,2} 65: {3,6} 107: {28} 29: {10} 67: {19} 109: {29} 31: {11} 71: {20} 111: {2,12} 37: {12} 73: {21} 113: {30}
Links
Crossrefs
Programs
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Mathematica
nn=100; dat=Select[Range[nn],CoprimeQ@@PrimePi/@First/@FactorInteger[#]&]; facsusing[s_,n_]:=If[n<=1,{{}},Join@@Table[Map[Prepend[#,d]&,Select[facsusing[Select[s,Divisible[n/d,#]&],n/d],Min@@#>=d&]],{d,Select[s,Divisible[n,#]&]}]]; Select[Range[nn],facsusing[dat,#]=={}&]
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