%I #17 Mar 25 2023 22:18:04
%S 9,41,51,109,483
%N Numbers k such that 89^k-88 is prime.
%C Related to hyperperfect numbers of a certain form.
%H J. S. McCranie, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL3/mccranie.html">A study of hyperperfect numbers</a>, J. Int. Seqs. Vol. 3 (2000) #P00.1.3.
%o (PARI) isok(n) = isprime(89^n-88); \\ _Michel Marcus_, Mar 12 2016
%K nonn,more
%O 1,1
%A _Jud McCranie_