220039211683domain: NAppears in sequencesLengths of successive words (starting with a) under the substitution: {a -> aab, b -> aac, c -> a}.at n=25A101168a(n) = 2*a(n-1) + 2*a(n-2) + a(n-3). a(0) = -1, a(1) = 1, a(2) = 1.at n=27A233828