306836domain: 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, -1, -1), (-1, -1, 0), (-1, -1, 1), (0, 1, 0), (1, 0, 1)}.at n=11A149847a(n) = a(n-1) + a(n-2) + n + 3 with n>1, a(0) = a(1) = 0.at n=23A210731