This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A138930 #4 Apr 18 2019 16:23:48
%S A138930 11,97,418993,28823037382718881,1980704062856484905159341969,
%T A138930 642775217703596110216784836917923148379301630095964749038433,
%U A138930 47428439751604713645494675459558567056117521481173860868835733244342769411181689
%N A138930 Primes of the form (8^n-3^n)/5.
%t A138930 a={}; Do[p=(8^n-3^n)/5; If[PrimeQ[p], AppendTo[a, p]], {n, 1, 10^2}]; a
%t A138930 Select[Table[(8^n-3^n)/5,{n,100}],PrimeQ] (* _Harvey P. Dale_, Apr 18 2019 *)
%Y A138930 Cf. A128025.
%K A138930 nonn
%O A138930 1,1
%A A138930 _Vladimir Joseph Stephan Orlovsky_, May 16 2008