Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (0, 0, -1), (0, 1, 0), (1, 0, 1)}.
A149946
Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (0, 0, -1), (0, 1, 0), (1, 0, 1)}.
Terms
- a(0) =1a(1) =2a(2) =5a(3) =15a(4) =50a(5) =169a(6) =582a(7) =2060a(8) =7422a(9) =27036a(10) =99396a(11) =368485a(12) =1375316a(13) =5162128a(14) =19472276a(15) =73760245a(16) =280411398a(17) =1069469986a(18) =4090621127a(19) =15686273759a(20) =60288482091a(21) =232187218317a(22) =895879809936
External references
- oeis: A149946