117531domain: NAppears in sequencesNumber 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, 0, 1), (1, -1, 1), (1, 1, -1)}.at n=10A148494a(n) = Sum_{k=0..floor(n/4)} 2^k * 3^(n-3*k) * binomial(2*(n-3*k),2*k).at n=9A391757