635569domain: NAppears in sequencesNumber of 2's in n-th "Kolakoski" string defined in A054349.at n=33A111123Constant term of the reduction by x^2 -> x+1 of the polynomial p(n,x) defined at Comments.at n=24A192960a(n) = (-1)^n + Sum_{k=0..floor((n-1)/2)} a(k) * a(n-2*k-1).at n=43A351973