Number of walks within N^2 (the first quadrant of Z^2) starting at (0,0), ending on the vertical axis and consisting of n steps taken from {(-1, 0), (-1, 1), (0, 1), (1, -1), (1, 0), (1, 1)}.
A151487
Number of walks within N^2 (the first quadrant of Z^2) starting at (0,0), ending on the vertical axis and consisting of n steps taken from {(-1, 0), (-1, 1), (0, 1), (1, -1), (1, 0), (1, 1)}.
Terms
- a(0) =1a(1) =1a(2) =5a(3) =15a(4) =73a(5) =295a(6) =1453a(7) =6709a(8) =33727a(9) =166433a(10) =854781a(11) =4380061a(12) =22915615a(13) =120259717a(14) =638778193a(15) =3408006119a(16) =18324864455a(17) =98963982349a(18) =537422614247
External references
- oeis: A151487