A069449 Half the number of 4 X n binary arrays with no path of adjacent 1's or adjacent 0's from top to bottom or side to side.

7, 269, 5799, 95783, 1389619, 18772467, 243194821, 3070812013

Offset

2,1

Links

Table of n, a(n) for n=2..9.

Crossrefs

Cf. 2 X n A000225, 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.

Sequence in context: A048291 A015089 A179565 * A100465 A140031 A066413

Adjacent sequences: A069446 A069447 A069448 * A069450 A069451 A069452

Keyword

nonn

Author

R. H. Hardin, Mar 22 2002

Status

approved