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, 1), (0, -1), (0, 1), (1, -1)}.
A151434
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, 1), (0, -1), (0, 1), (1, -1)}.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =4a(4) =12a(5) =30a(6) =100a(7) =285a(8) =1018a(9) =3142a(10) =11736a(11) =38276a(12) =147552a(13) =501072a(14) =1977608a(15) =6926828a(16) =27842000a(17) =99938263a(18) =407596014a(19) =1492448436a(20) =6159941412a(21) =22930113936a(22) =95587448784a(23) =360799985580
External references
- oeis: A151434