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 A069418 #9 Apr 07 2021 18:46:50 %S A069418 1,39,907,17339,300651,4927163,77892523,1201461339 %N A069418 Number of 4 X n binary arrays with a path of adjacent 1's and no path of adjacent 0's from top row to bottom row. %Y A069418 Cf. 2 X n A001047, n X 2 A034182, vertical path of 1 A069361-A069395, vertical paths of 0+1 A069396-A069416, vertical path of 1 not 0 A069417-A069428, no vertical paths A069429-A069447, no horizontal or vertical paths A069448-A069452. %K A069418 nonn %O A069418 1,2 %A A069418 _R. H. Hardin_, Mar 22 2002