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 A308886 #5 Jul 01 2019 22:56:00 %S A308886 4,5,6,9,10,11,12,15,21,24,31,34,44,58,61,64,66,67,68,69,71,72,75,78, %T A308886 80,81,82,84,85,86,87,89,90,93,96,99,100,109,111,120,122,131,133,136, %U A308886 139,142,161,164,187,190,196,198,200,201,202,203,204,205,207,209,210,211,213,215 %N A308886 Positions of 1's on the spiral defined in A308884. %Y A308886 Cf. A308884-A308895. %K A308886 nonn %O A308886 1,1 %A A308886 _N. J. A. Sloane_, Jul 01 2019