50146domain: NAppears in sequencesG.f.: x^2*(1-x)*(1-4*x+4*x^2+x^3)/((1-2*x)^2*(1-3*x+x^2)).at n=13A229737Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 283", based on the 5-celled von Neumann neighborhood.at n=41A271119