OFFSET
1,2
MATHEMATICA
Do[ If[ PrimeQ[(3^n + 5) / 2], Print[n] ], {n, 0, 3000} ]
Select[Range[0, 10000], PrimeQ[(3^# + 5)/2] &] (* Vincenzo Librandi, Sep 29 2012 *)
PROG
(PARI) is(n)=ispseudoprime((3^n+5)/2) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Robert G. Wilson v, Jan 13 2001
EXTENSIONS
Added a(1)=0 and a(19)-a(21) from Vincenzo Librandi, Sep 29 2012
a(22)-a(24) from Jinyuan Wang, Jan 27 2020
a(25) from Michael S. Branicky, Apr 24 2023
a(26) from Michael S. Branicky, Oct 17 2024
STATUS
approved