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 A246492 #8 Sep 06 2014 00:19:38 %S A246492 2,5,11,23,47,283,719,1439,2879,34549,138197,1266767,4782969,14348907 %N A246492 Smallest k such that 4^^n is not congruent to 4^^(n-1) mod k, where 4^^n denotes the power tower 4^4^...^4 (in which 4 appears n times). %C A246492 For general remarks regarding sequences of this type, see A246491. %o A246492 (Sage, cython) Use linked source from A246491 with this command: find_k_values(4,1,1) %Y A246492 Cf. A027763, A246491, A246493, A246494, A246495, A246496, A246497 %K A246492 nonn,more %O A246492 1,1 %A A246492 _Wayne VanWeerthuizen_, Aug 27 2014