112043domain: NAppears in sequencesa(n) = a(n-1) + a(n-2) + 1, with a(0) = 1 and a(1) = 8.at n=21A022322Define two sequences by A_n = mex{A_i,B_i : 0 <= i < n} for n >= 0, B_0=0, B_1=1 and for n >= 2, B_n = 2B_{n-1}+(-1)^{A_n}. Sequence gives B_n.at n=17A080241G.f. satisfies A(x) = 1 + x*A(x)^3 / (1 - x*A(x)^2)^2.at n=7A367238