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, 1, -1), (0, 1, 0), (1, 0, 1)}.
A149968
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, 1, -1), (0, 1, 0), (1, 0, 1)}.
Terms
- a(0) =1a(1) =2a(2) =5a(3) =16a(4) =55a(5) =188a(6) =674a(7) =2471a(8) =9067a(9) =33926a(10) =128156a(11) =484224a(12) =1847218a(13) =7084777a(14) =27186054a(15) =104885416a(16) =405958461a(17) =1572023508a(18) =6108058902a(19) =23783305717a(20) =92648913045a(21) =361724652715
External references
- oeis: A149968