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, -1), (-1, 1), (0, 1), (1, -1), (1, 0), (1, 1)}.
A151481
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, -1), (-1, 1), (0, 1), (1, -1), (1, 0), (1, 1)}.
Terms
- a(0) =1a(1) =1a(2) =4a(3) =13a(4) =57a(5) =236a(6) =1106a(7) =5136a(8) =25112a(9) =123604a(10) =624229a(11) =3181337a(12) =16456910a(13) =85845734a(14) =452215297a(15) =2398829267a(16) =12815000375a(17) =68850087543a(18) =371908087035
External references
- oeis: A151481