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, 0), (-1, 1), (0, -1), (0, 1), (1, 1)}.
A151448
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, 0), (-1, 1), (0, -1), (0, 1), (1, 1)}.
Terms
- a(0) =1a(1) =1a(2) =4a(3) =13a(4) =46a(5) =178a(6) =699a(7) =2826a(8) =11665a(9) =48877a(10) =207426a(11) =889753a(12) =3850726a(13) =16792923a(14) =73721417a(15) =325516893a(16) =1444683024a(17) =6440892041a(18) =28832816045a(19) =129544987197a(20) =583978531063
External references
- oeis: A151448