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, 1, 0), (0, 1, -1), (1, 0, -1), (1, 1, 0)}.
A148685
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, 1, 0), (0, 1, -1), (1, 0, -1), (1, 1, 0)}.
Terms
- a(0) =1a(1) =1a(2) =3a(3) =7a(4) =22a(5) =66a(6) =227a(7) =768a(8) =2771a(9) =10025a(10) =37661a(11) =142117a(12) =548827a(13) =2135363a(14) =8429552a(15) =33539945a(16) =134793466a(17) =545473164a(18) =2224521240a(19) =9126088552a(20) =37669774713a(21) =156291183756a(22) =651703333129
External references
- oeis: A148685