Number of open knight's tour diagrams of a 3 X n chessboard that are symmetric under 180-degree rotation and have "type F": the endpoints occur in different columns and agree in color with the cells in the nearest corner.
A169774
Number of open knight's tour diagrams of a 3 X n chessboard that are symmetric under 180-degree rotation and have "type F": the endpoints occur in different columns and agree in color with the cells in the nearest corner.
Terms
- a(0) =2a(1) =0a(2) =0a(3) =4a(4) =12a(5) =20a(6) =28a(7) =120a(8) =104a(9) =304a(10) =384a(11) =1304a(12) =1680a(13) =4936a(14) =5908a(15) =18304a(16) =21412a(17) =63440a(18) =76920a(19) =233248a(20) =281284a(21) =833720a(22) =990104a(23) =2993016a(24) =3523740a(25) =10485472a(26) =12432392a(27) =37485424a(28) =44184884a(29) =131430320
External references
- oeis: A169774