Safe perfect powers: perfect powers n such that (n-1)/2 is also a perfect power.

A075127

Safe perfect powers: perfect powers n such that (n-1)/2 is also a perfect power.

Terms

    a(0) =9a(1) =243a(2) =289a(3) =9801a(4) =332929a(5) =11309769a(6) =384199201a(7) =13051463049a(8) =443365544449

External references