255934domain: NAppears in sequencesa(n) is the number of binary strings of length n such that no subsequence of length 5 or less contains 4 or more ones.at n=19A125513G.f.: 1/(1 - x/(1 - x^3/(1 - x^4/(1 - x^7/(1 - x^11/(1 - x^18/(1 -...- x^Lucas(n)/(1 -...)))))))), a continued fraction.at n=32A206742