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, 0), (0, -1), (1, -1), (1, 0), (1, 1)}.
A151475
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, 0), (0, -1), (1, -1), (1, 0), (1, 1)}.
Terms
- a(0) =1a(1) =0a(2) =3a(3) =2a(4) =23a(5) =35a(6) =258a(7) =591a(8) =3538a(9) =10378a(10) =55110a(11) =189260a(12) =937965a(13) =3566795a(14) =17014249a(15) =69167067a(16) =323493034a(17) =1374890250a(18) =6373894066a(19) =27922300363a(20) =129121327852a(21) =577728005802
External references
- oeis: A151475