%I #9 Apr 07 2021 18:48:20

%S 1048575,1096024843375,1117982939085627425,1092719640470296684383473

%N Number of n X 20 binary arrays with a path of adjacent 1's from top row to bottom row.

%Y Cf. 1 X n A000225, 2 X n A005061, n X 2 A001333, 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 nonn

%O 1,1

%A _R. H. Hardin_, Mar 22 2002