4527185domain: NAppears in sequencesBase-4 digits are, in order, the first n terms of the periodic sequence with initial period 1,0,1.at n=11A033122Base 8 digits are, in order, the first n terms of the periodic sequence with initial period 2,1.at n=7A037493a(n) = Sum_{1<=k<=n, gcd(k,n)=1} 2^(k-1).at n=23A054432