105226698752domain: NAppears in sequencesExpansion of (1 + 2*x)/(1 - 2*x)^3.at n=27A014477Decimal representation of the diagonal from the origin to the corner of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 270", based on the 5-celled von Neumann neighborhood.at n=42A287467