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, 0), (-1, 1, 1), (0, 1, 0), (1, 0, 0), (1, 1, -1)}.
A149974
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, 0), (-1, 1, 1), (0, 1, 0), (1, 0, 0), (1, 1, -1)}.
Terms
- a(0) =1a(1) =2a(2) =5a(3) =16a(4) =56a(5) =204a(6) =786a(7) =3128a(8) =12711a(9) =52785a(10) =222949a(11) =953417a(12) =4126429a(13) =18040639a(14) =79526717a(15) =353268588a(16) =1579911721a(17) =7107040619a(18) =32142739964a(19) =146077453326a(20) =666745748346
External references
- oeis: A149974