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

A149724

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

Terms

    a(0) =1a(1) =1a(2) =5a(3) =17a(4) =75a(5) =285a(6) =1317a(7) =5567a(8) =25985a(9) =114405a(10) =542049a(11) =2456039a(12) =11720847a(13) =54060867a(14) =259872549a(15) =1214918367a(16) =5866220625a(17) =27689646713a(18) =134259837463a(19) =638654468767

External references