OFFSET
1,2
COMMENTS
EXAMPLE
Most small numbers are in the sequence. However, the sequence of non-terms together with their prime indices begins:
12: {1,1,2}
24: {1,1,1,2}
30: {1,2,3}
36: {1,1,2,2}
40: {1,1,1,3}
48: {1,1,1,1,2}
60: {1,1,2,3}
63: {2,2,4}
70: {1,3,4}
72: {1,1,1,2,2}
80: {1,1,1,1,3}
84: {1,1,2,4}
90: {1,2,2,3}
96: {1,1,1,1,1,2}
MATHEMATICA
primeMS[n_]:=If[n==1, {}, Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]];
Select[Range[100], UnsameQ@@Total/@Union[ReplaceList[primeMS[#], {___, s__, ___}:>{s}]]&]
CROSSREFS
KEYWORD
nonn
AUTHOR
Gus Wiseman, May 20 2019
STATUS
approved