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), (0, -1), (0, 1), (1, 0), (1, 1)}.
A151455
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), (0, -1), (0, 1), (1, 0), (1, 1)}.
Terms
- a(0) =1a(1) =1a(2) =4a(3) =11a(4) =41a(5) =148a(6) =572a(7) =2267a(8) =9162a(9) =37891a(10) =158433a(11) =672432a(12) =2879455a(13) =12450139a(14) =54227938a(15) =237810937a(16) =1049050916a(17) =4651766238a(18) =20724281904a(19) =92714185721a(20) =416353436502
External references
- oeis: A151455