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), (1, 0), (1, 1)}.
A151441
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), (1, 0), (1, 1)}.
Terms
- a(0) =1a(1) =1a(2) =4a(3) =12a(4) =47a(5) =176a(6) =731a(7) =2988a(8) =12813a(9) =55048a(10) =241623a(11) =1067940a(12) =4776698a(13) =21504298a(14) =97577393a(15) =445194901a(16) =2042702372a(17) =9415233073a(18) =43584936370a(19) =202517766967a(20) =944273642108
External references
- oeis: A151441