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 A026228 #7 Jul 04 2021 13:04:37 %S A026228 2,5,11,14,23,29,32,38,41,50,59,65,68,77,83,86,92,95,104,110,113,119, %T A026228 122,131,140,146,149,158,167,173,176,185,191,194,200,203,212,221,227, %U A026228 230,239,245,248,254,257,266,272,275,281,284 %N A026228 Numbers k such that A026166(k) = A026136(k) - 1. %K A026228 nonn %O A026228 1,1 %A A026228 _Clark Kimberling_