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 A266234 #8 Jan 09 2016 14:28:09
%S A266234 3,5,13,17,37,41,61,73,89,97,113,157,193,233,241,257,277,281,313,337,
%T A266234 353,397,401,409,421,433,449,457,521,541,577,593,601,613,641,661,673,
%U A266234 733,757,761,769,877,929,953,997,1009,1049,1093,1129,1153,1201,1213,1237
%N A266234 Primes representable as f(f(f(...f(p)...))) where p is a prime and f(x) = x*2 - 1.
%C A266234 A005383 is a subsequence: f(x) is applied just once.
%t A266234 Take[Union@ Flatten[Table[Nest[2 # - 1 &, Prime@ n, #], {n, 120}] & /@ Range@ 120] /. n_ /; CompositeQ@ n -> Nothing, 53] (* _Michael De Vlieger_, Jan 06 2016 *)
%Y A266234 Cf. A000040, A005383, A266233.
%K A266234 nonn
%O A266234 1,1
%A A266234 _Alex Ratushnyak_, Dec 25 2015