371370domain: NAppears in sequencesa(n) = Sum_{k=0..n} A026626(n, k).at n=18A026633a(n) = Sum_{k=0..floor(n/2)} A026626(n, k).at n=19A026634Decimal representation of the middle column of the "Rule 59" elementary cellular automaton starting with a single ON (black) cell.at n=18A266721