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, 0, 1), (1, 0, -1)}.
A148073
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, 0, 1), (1, 0, -1)}.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =4a(4) =9a(5) =21a(6) =56a(7) =153a(8) =431a(9) =1269a(10) =3748a(11) =11283a(12) =34892a(13) =109201a(14) =346671a(15) =1113914a(16) =3599997a(17) =11754161a(18) =38738445a(19) =128543670a(20) =429827021a(21) =1444670782a(22) =4879545858a(23) =16575721093a(24) =56568953256a(25) =193962159926a(26) =667744908521
External references
- oeis: A148073