Number of nX4 arrays of occupancy after each element moves to some horizontal or antidiagonal neighbor, without 2-loops or left turns.
A221783
Number of nX4 arrays of occupancy after each element moves to some horizontal or antidiagonal neighbor, without 2-loops or left turns.
Terms
- a(0) =0a(1) =3a(2) =5a(3) =16a(4) =41a(5) =105a(6) =288a(7) =735a(8) =1981a(9) =5156a(10) =13685a(11) =35973a(12) =94940a(13) =250271a(14) =659721a(15) =1739740a(16) =4585933a(17) =12092245a(18) =31878636a(19) =84050611a(20) =221594145a(21) =584232168a(22) =1540316025
External references
- oeis: A221783