Number of walks within N^2 (the first quadrant of Z^2) starting and ending at (0,0) and consisting of 2 n steps taken from {(-1, -1), (-1, 0), (-1, 1), (1, -1), (1, 1)}.
A151345
Number of walks within N^2 (the first quadrant of Z^2) starting and ending at (0,0) and consisting of 2 n steps taken from {(-1, -1), (-1, 0), (-1, 1), (1, -1), (1, 1)}.
Terms
- a(0) =1a(1) =1a(2) =6a(3) =55a(4) =644a(5) =8694a(6) =128964a(7) =2045901a(8) =34136960a(9) =592493044a(10) =10614366568a(11) =195164993478
External references
- oeis: A151345