OFFSET
1,1
EXAMPLE
The non-prime-powers (inclusive) are 6, 10, 12, 14, 15, 18, 20, 21, 22, 24, ... which increase by 1 after positions 4, 7, 8, ...
MATHEMATICA
ce=Select[Range[2, 100], !PrimePowerQ[#]&];
Select[Range[Length[ce]-1], ce[[#+1]]==ce[[#]]+1&]
CROSSREFS
KEYWORD
nonn
AUTHOR
Gus Wiseman, Sep 13 2024
STATUS
approved