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, 0, -1), (0, 1, 0), (1, 0, 0)}.
A149919
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, 0, -1), (0, 1, 0), (1, 0, 0)}.
Terms
- a(0) =1a(1) =2a(2) =5a(3) =15a(4) =47a(5) =157a(6) =549a(7) =1982a(8) =7354a(9) =27927a(10) =107979a(11) =424329a(12) =1690034a(13) =6812041a(14) =27739662a(15) =114012290a(16) =472388018a(17) =1971765577a(18) =8284065362a(19) =35014751268a(20) =148798722863a(21) =635518054040
External references
- oeis: A149919