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 A106745 #10 Dec 15 2017 17:36:47 %S A106745 5,6,7,12,21,25,300,305,600,689,742,1418,1547,1744,5275,6355,7477, %T A106745 15312,16772,33047 %N A106745 Numbers n such that 101101 * 10^n + 1 is prime. %C A106745 These are anti-Yarborough primes, i.e. primes containing just 1's and 0's and they have all been certified. Primality proof for the largest: PFGW Version 20041001.Win_Stable (v1.2 RC1b) [FFT v23.8] Primality testing 101101*10^33047+1 [N-1, Brillhart-Lehmer-Selfridge] Running N-1 test using base 3 Calling Brillhart-Lehmer-Selfridge with factored part 69.89% 101101*10^33047+1 is prime! (194.9694s+0.0907s) %H A106745 R. Ondrejka, <a href="http://www.utm.edu/research/primes/lists/top_ten/">The Top Ten: a Catalogue of Primal Configurations</a>. %o A106745 (PARI) is(n)=ispseudoprime(101101*10^n+1) \\ _Charles R Greathouse IV_, Jun 06 2017 %Y A106745 Cf. A020449. %K A106745 nonn,more %O A106745 1,1 %A A106745 _Jason Earls_, May 16 2005