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

A149406

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

Terms

    a(0) =1a(1) =1a(2) =4a(3) =12a(4) =52a(5) =190a(6) =850a(7) =3433a(8) =15725a(9) =67088a(10) =312593a(11) =1379704a(12) =6507124a(13) =29391737a(14) =139840831a(15) =642273010a(16) =3075896765a(17) =14305813433a(18) =68859801542a(19) =323395442425

External references