A367227 Numbers m whose prime indices have no nonnegative linear combination equal to bigomega(m).
3, 5, 7, 11, 13, 17, 19, 23, 25, 27, 29, 31, 35, 37, 41, 43, 47, 49, 53, 55, 59, 61, 63, 65, 67, 71, 73, 77, 79, 83, 85, 89, 91, 95, 97, 99, 101, 103, 107, 109, 113, 115, 117, 119, 121, 127, 131, 133, 137, 139, 143, 145, 147, 149, 151, 153, 155, 157, 161, 163
Offset: 1
Keywords
Examples
The prime indices of 24 are {1,1,1,2} with (1+1+1+1) = 4 or (1+1)+(2) = 4 or (2+2) = 4, so 24 is not in the sequence. The terms together with their prime indices begin: 3: {2} 43: {14} 85: {3,7} 5: {3} 47: {15} 89: {24} 7: {4} 49: {4,4} 91: {4,6} 11: {5} 53: {16} 95: {3,8} 13: {6} 55: {3,5} 97: {25} 17: {7} 59: {17} 99: {2,2,5} 19: {8} 61: {18} 101: {26} 23: {9} 63: {2,2,4} 103: {27} 25: {3,3} 65: {3,6} 107: {28} 27: {2,2,2} 67: {19} 109: {29} 29: {10} 71: {20} 113: {30} 31: {11} 73: {21} 115: {3,9} 35: {3,4} 77: {4,5} 117: {2,2,6} 37: {12} 79: {22} 119: {4,7} 41: {13} 83: {23} 121: {5,5}
Crossrefs
The following sequences count and rank integer partitions and finite sets according to whether their length is a subset-sum or linear combination of the parts. The current sequence is starred.
sum-full sum-free comb-full comb-free
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Programs
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Mathematica
prix[n_]:=If[n==1,{}, Flatten[Cases[FactorInteger[n], {p_,k_}:>Table[PrimePi[p], {k}]]]]; combs[n_,y_]:=With[{s=Table[{k,i}, {k,y}, {i,0,Floor[n/k]}]}, Select[Tuples[s], Total[Times@@@#]==n&]]; Select[Range[100], combs[PrimeOmega[#], Union[prix[#]]]=={}&]
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