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, 0, 1), (-1, 1, -1), (1, -1, 1), (1, 1, 0)}.

A149217

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, 0, 1), (-1, 1, -1), (1, -1, 1), (1, 1, 0)}.

Terms

    a(0) =1a(1) =1a(2) =4a(3) =10a(4) =42a(5) =136a(6) =598a(7) =2162a(8) =9815a(9) =37636a(10) =174615a(11) =694695a(12) =3271551a(13) =13352629a(14) =63547908a(15) =264327829a(16) =1267696988a(17) =5350969987a(18) =25811875559a(19) =110238766866a(20) =534157611947

External references