OFFSET
1,3
COMMENTS
EXAMPLE
The prime indices of 360 are {1,1,1,2,2,3}, with mean 3/2, so a(360) = 2.
MATHEMATICA
prix[n_]:=If[n==1, {}, Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]];
meanup[y_]:=If[Length[y]==0, 0, Ceiling[Mean[y]]];
Table[meanup[prix[n]], {n, 100}]
CROSSREFS
Positions of first appearances are 1 and A000040.
Positions of 1's are A000079(n>0).
The triangle for this statistic (high mean) is A363946.
A360005 gives twice the median of prime indices.
KEYWORD
nonn
AUTHOR
Gus Wiseman, Jun 30 2023
STATUS
approved