Number of walks of length 4n in the first octant using steps (1,1,1), (-1,0,0), (0,-1,0), and (0,0,-1) that start and end at the origin.

A340540

Number of walks of length 4n in the first octant using steps (1,1,1), (-1,0,0), (0,-1,0), and (0,0,-1) that start and end at the origin.

Terms

    a(0) =1a(1) =6a(2) =288a(3) =24444a(4) =2738592a(5) =361998432a(6) =53414223552

External references