Number of walks within N^2 (the first quadrant of Z^2) starting at (0,0) and consisting of n steps taken from {(-1, -1), (-1, 1), (-1, 0), (0, -1), (0, 1), (1, -1), (1, 0), (1, 1)}.
A151331
Number of walks within N^2 (the first quadrant of Z^2) starting at (0,0) and consisting of n steps taken from {(-1, -1), (-1, 1), (-1, 0), (0, -1), (0, 1), (1, -1), (1, 0), (1, 1)}.
Terms
- a(0) =1a(1) =3a(2) =18a(3) =105a(4) =684a(5) =4550a(6) =31340a(7) =219555a(8) =1564080a(9) =11271876a(10) =82059768a(11) =602215614a(12) =4450146624a(13) =33076800900a(14) =247096919784
External references
- oeis: A151331