Number of walks within N^2 (the first quadrant of Z^2) starting at (0,0), ending on the vertical axis and consisting of 2 n steps taken from {(-1, -1), (-1, 0), (1, 0), (1, 1)}.
A151388
Number of walks within N^2 (the first quadrant of Z^2) starting at (0,0), ending on the vertical axis and consisting of 2 n steps taken from {(-1, -1), (-1, 0), (1, 0), (1, 1)}.
Terms
- a(0) =1a(1) =3a(2) =21a(3) =193a(4) =2034a(5) =23283a(6) =281688a(7) =3545919a(8) =45988056a(9) =610459630a(10) =8255756937a(11) =113365682625
External references
- oeis: A151388