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, 0, 0), (0, 1, 1), (1, -1, 0), (1, 1, -1)}.
A148939
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, 0, 0), (0, 1, 1), (1, -1, 0), (1, 1, -1)}.
Terms
- a(0) =1a(1) =1a(2) =3a(3) =9a(4) =29a(5) =97a(6) =337a(7) =1200a(8) =4352a(9) =15964a(10) =59163a(11) =221154a(12) =832740a(13) =3153898a(14) =12001752a(15) =45860585a(16) =175873274a(17) =676595506a(18) =2610061582a(19) =10092824792a(20) =39110984254a(21) =151848868126a(22) =590564253255
External references
- oeis: A148939