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 A256622 #27 Mar 19 2018 05:41:48 %S A256622 9632552297,23971039429,32460766253,55325366053,75883883641, %T A256622 87824771197,91754975491,91989527023,97696323983 %N A256622 Primes p such that the decimal expansion of p remains prime under four iterations of base-10 to base-2 conversion. %C A256622 Jim Fougeron and _Farideh Firoozbakht_ independently found the first term 9632552297. %C A256622 When does five iterations start? %H A256622 Carlos Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_280.htm">Puzzle 280</a>, The Prime Puzzles & Problems Connection. %Y A256622 Cf. A065720, A123266, A256621. %K A256622 nonn,base,hard,more %O A256622 1,1 %A A256622 _Sebastian Petzelberger_, Apr 07 2015