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 A205670 #12 Dec 07 2019 14:53:32 %S A205670 1,4,20,31 %N A205670 Possibly optimal shellsort sequence for reverse-sorting an ascending list of size N=32. %C A205670 This is a (possibly) optimal sequence for reverse-sorting an ascending list where N = 32. Requires 3.313*N comparisons. 3.313 is approximately equal to 2.21*log_10(32). The operation performed requires a defined, substantial and certainly nontrivial amount of work which is repeatable for a list of any size. %D A205670 Sequences A204772 where N=128 and A205669 where N=64. %K A205670 nonn %O A205670 1,2 %A A205670 _Olof Forshell_, Jan 30 2012