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, 0), (0, -1), (0, 1), (1, -1), (1, 0)}.
A151297
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, 0), (0, -1), (0, 1), (1, -1), (1, 0)}.
Terms
- a(0) =1a(1) =2a(2) =7a(3) =26a(4) =105a(5) =444a(6) =1944a(7) =8728a(8) =39999a(9) =186266a(10) =879108a(11) =4195762a(12) =20217136a(13) =98220992a(14) =480623748a(15) =2366735352a(16) =11720044199a(17) =58329063714a(18) =291607308864
External references
- oeis: A151297