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, 0), (-1, 0, 1), (0, 1, 0), (1, -1, 1), (1, 0, -1)}.
A148399
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, 0), (-1, 0, 1), (0, 1, 0), (1, -1, 1), (1, 0, -1)}.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =5a(4) =16a(5) =54a(6) =192a(7) =720a(8) =2703a(9) =10516a(10) =41705a(11) =168001a(12) =689349a(13) =2859808a(14) =12006070a(15) =50816519a(16) =217011153a(17) =932736893a(18) =4035832654a(19) =17565418331a(20) =76834165053a(21) =337790073171
External references
- oeis: A148399