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, 0), (0, 1), (1, 0), (1, 1)}.
A151432
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, 0), (0, 1), (1, 0), (1, 1)}.
Terms
- a(0) =1a(1) =1a(2) =4a(3) =12a(4) =45a(5) =174a(6) =693a(7) =2891a(8) =12156a(9) =52538a(10) =228973a(11) =1012996a(12) =4518961a(13) =20342820a(14) =92221108a(15) =420719274a(16) =1930067929a(17) =8897118329a(18) =41194214136a(19) =191470957420a(20) =893110958485
External references
- oeis: A151432