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, 0, 0), (0, -1, 0), (0, 1, -1), (1, 1, 1)}.
A149425
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, 0, 0), (0, -1, 0), (0, 1, -1), (1, 1, 1)}.
Terms
- a(0) =1a(1) =1a(2) =4a(3) =13a(4) =42a(5) =146a(6) =520a(7) =1893a(8) =6928a(9) =25520a(10) =95258a(11) =357332a(12) =1348314a(13) =5109674a(14) =19419422a(15) =74124571a(16) =283750244a(17) =1089053340a(18) =4189218564a(19) =16143369610a(20) =62342218516a(21) =241154261642a(22) =934254937426
External references
- oeis: A149425