A171719 - OEIS

%I #4 Dec 15 2017 17:37:10

%S 1,2,4,8,17,517,581,665,890,4901,5230,7515

%N Numbers n such that 10^n*(8+3*10^n)+3 is prime.

%C Values corresponding to n=4901, n=5230, and n=7515 were all certified Fermat and Lucas PRPs with WinPFGW and the latter two (>10k digits) were submitted to Lifchitz's Top PRPs database. No more terms up to n=8100.

%o (PARI) is(n)=ispseudoprime(10^n*(8+3*10^n)+3) \\ _Charles R Greathouse IV_, Jun 13 2017

%K more,nonn

%O 1,2

%A _Jason Earls_, Dec 16 2009