52195783domain: NAppears in sequencesBase 4 digits are, in order, the first n terms of the periodic sequence with initial period 3,0,1.at n=12A037646a(n) = a(n-1) + 2^A047240(n) for n>1, a(1)=1.at n=13A113841a(0) = 0, a(n+1) = 2*a(n) + (-1)^floor(n/3).at n=26A275788