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), (-1, -1, 0), (-1, 1, -1), (1, -1, 0), (1, 1, 1)}.
A149521
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), (-1, -1, 0), (-1, 1, -1), (1, -1, 0), (1, 1, 1)}.
Terms
- a(0) =1a(1) =1a(2) =5a(3) =11a(4) =51a(5) =147a(6) =691a(7) =2229a(8) =10569a(9) =36587a(10) =174151a(11) =631267a(12) =3015819a(13) =11297343a(14) =54109527a(15) =207809319a(16) =997352927a(17) =3905712813a(18) =18775928973a(19) =74694466147a(20) =359566404155
External references
- oeis: A149521