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)}.
A151436
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) =4a(3) =11a(4) =44a(5) =153a(6) =638a(7) =2443a(8) =10468a(9) =42306a(10) =184576a(11) =772024a(12) =3411966a(13) =14612580a(14) =65212028a(15) =284126776a(16) =1277710146a(17) =5639805613a(18) =25519441118a(19) =113792116639a(20) =517542778146
External references
- oeis: A151436