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), (1, 0, -1), (1, 1, 1)}.

A149263

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), (1, 0, -1), (1, 1, 1)}.

Terms

    a(0) =1a(1) =1a(2) =4a(3) =11a(4) =40a(5) =128a(6) =484a(7) =1641a(8) =6334a(9) =22270a(10) =86616a(11) =312454a(12) =1220466a(13) =4479292a(14) =17560954a(15) =65232393a(16) =256488726a(17) =961512650a(18) =3788566998a(19) =14305980766a(20) =56457883232a(21) =214441375622a(22) =847362995744

External references