A366128 Least non-subset-sum of the multiset of prime indices of n.
0, 0, 1, 0, 1, 0, 1, 0, 1, 2, 1, 0, 1, 2, 1, 0, 1, 0, 1, 0, 1, 2, 1, 0, 1, 2, 1, 3, 1, 0, 1, 0, 1, 2, 1, 0, 1, 2, 1, 0, 1, 0, 1, 3, 1, 2, 1, 0, 1, 2, 1, 3, 1, 0, 1, 0, 1, 2, 1, 0, 1, 2, 1, 0, 1, 4, 1, 3, 1, 2, 1, 0, 1, 2, 1, 3, 1, 4, 1, 0, 1, 2, 1, 0, 1, 2, 1
Offset: 1
Keywords
Examples
The prime indices of 3906 are {1,2,2,4,11}, with least non-subset-sum 10, so a(3906) = 10.
Crossrefs
Positions of ones are A005408.
Positions of twos appear to be A091999.
For greatest instead of least we have A365920 (Frobenius number).
The triangle for this rank statistic is A365921 (partitions with least non-subset-sum k).
A055932 lists numbers whose prime indices cover an initial interval.
A073491 lists numbers with gap-free prime indices.
Programs
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Mathematica
prix[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]]; nmz[y_]:=Complement[Range[Total[y]],Total/@Subsets[y]]; Table[If[nmz[prix[n]]=={},0,Min@@nmz[prix[n]]],{n,100}]
Comments