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), (-1, 0, 1), (0, 0, 1), (1, -1, 0), (1, 1, -1)}.
A148481
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), (-1, 0, 1), (0, 0, 1), (1, -1, 0), (1, 1, -1)}.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =6a(4) =20a(5) =73a(6) =272a(7) =1040a(8) =4177a(9) =17264a(10) =72861a(11) =311631a(12) =1349356a(13) =5922851a(14) =26295985a(15) =117817978a(16) =531665582a(17) =2415053676a(18) =11040435677a(19) =50762362640a(20) =234552661491
External references
- oeis: A148481