225948domain: NAppears in sequencesExpansion of (1-x)/(1-x-3*x^2).at n=16A052533Number 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, 0), (0, 1, -1), (1, 0, 0), (1, 1, 1)}.at n=9A150766a(0)=1, a(1)=3, a(n) = 7*a(n-1) - 9*a(n-2) for n > 1.at n=8A165310