Number of walks within N^2 (the first quadrant of Z^2) starting at (0,0) and consisting of n steps taken from {(-1, -1), (-1, 0), (0, -1), (1, -1), (1, 0), (1, 1)}.
A151309
Number of walks within N^2 (the first quadrant of Z^2) starting at (0,0) and consisting of n steps taken from {(-1, -1), (-1, 0), (0, -1), (1, -1), (1, 0), (1, 1)}.
Terms
- a(0) =1a(1) =2a(2) =9a(3) =35a(4) =160a(5) =720a(6) =3413a(7) =16220a(8) =78941a(9) =386168a(10) =1913966a(11) =9534469a(12) =47882879a(13) =241540800a(14) =1225176455a(15) =6237701908a(16) =31886453967a(17) =163506199839a(18) =841042932257
External references
- oeis: A151309