OFFSET
1,1
EXAMPLE
The initial non-prime-powers are 1, 6, 10, 12, 14, 15, 18, 20, 21, which first increase by one after the fifth and eighth terms.
MATHEMATICA
Join@@Position[Differences[Select[Range[100], !PrimePowerQ[#]&]], 1]
CROSSREFS
KEYWORD
nonn
AUTHOR
Gus Wiseman, Sep 02 2024
STATUS
approved