Number of n X 2 arrays of occupancy after each element moves to some horizontal or vertical neighbor, without consecutive moves in the same direction.
A221425
Number of n X 2 arrays of occupancy after each element moves to some horizontal or vertical neighbor, without consecutive moves in the same direction.
Terms
- a(0) =1a(1) =9a(2) =42a(3) =217a(4) =1116a(5) =5722a(6) =29383a(7) =150821a(8) =774219a(9) =3974308a(10) =20401353a(11) =104726538a(12) =537593996a(13) =2759637891a(14) =14166083083a(15) =72718928341a(16) =373288968420
External references
- oeis: A221425