Number of nX4 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 0 and 1 0 1 vertically.
A207781
Number of nX4 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 0 and 1 0 1 vertically.
Terms
- a(0) =9a(1) =81a(2) =257a(3) =791a(4) =2200a(5) =6418a(6) =19041a(7) =55101a(8) =160274a(9) =468839a(10) =1365913a(11) =3979457a(12) =11607265a(13) =33840611a(14) =98648082a(15) =287610828a(16) =838518475a(17) =2444629303a(18) =7127128826a(19) =20778544998a(20) =60578554943a(21) =176612608043a(22) =514899479923
External references
- oeis: A207781