522751domain: NAppears in sequencesa(n) = 2^(2*n+1) - 3*2^n - 1.at n=8A195460Decimal 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 531", based on the 5-celled von Neumann neighborhood.at n=18A288976