Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (-1, 0, 0), (0, 1, 0), (0, 1, 1), (1, 0, -1)}.
A149949
Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (-1, 0, 0), (0, 1, 0), (0, 1, 1), (1, 0, -1)}.
Terms
- a(0) =1a(1) =2a(2) =5a(3) =15a(4) =50a(5) =175a(6) =643a(7) =2442a(8) =9497a(9) =37772a(10) =152757a(11) =626466a(12) =2602060a(13) =10918685a(14) =46235865a(15) =197396778a(16) =848640258a(17) =3671712505a(18) =15976961310a(19) =69874586990a(20) =307024031593
External references
- oeis: A149949