a(n) is the number of lattice walks from (0,0) to (3*n,3*n) that use steps in directions {(3,0), (2,1), (1,2), (0,3)} and stay weakly below the line y=x.
A292437
a(n) is the number of lattice walks from (0,0) to (3*n,3*n) that use steps in directions {(3,0), (2,1), (1,2), (0,3)} and stay weakly below the line y=x.
Terms
- a(0) =1a(1) =2a(2) =13a(3) =120a(4) =1288a(5) =15046a(6) =185658a(7) =2380720a(8) =31411376a(9) =423660504a(10) =5814905977a(11) =80956085304
External references
- oeis: A292437