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 A267375 #25 Jun 13 2017 14:31:29 %S A267375 127,18013,39623 %N A267375 Numbers n such that (47^n - 1)/46 is prime. %o A267375 (PARI) is(n)=ispseudoprime((47^n-1)/46) \\ _Charles R Greathouse IV_, Jun 13 2017 %K A267375 nonn,more,hard %O A267375 1,1 %A A267375 _Tim Johannes Ohrtmann_, Feb 22 2016