151005domain: NAppears in sequencesa(n) = (25*n^4-120*n^3+209*n^2-108*n)/6.at n=15A006529Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, 0, 0), (-1, 1, 1), (0, -1, 1), (1, 0, -1), (1, 1, 1)}.at n=9A149784