T1:={[i,j]->[j,i,0]};
T2:={[i,j]->[j,i,1]};
R2:={[i,j]: 1 <= i,j <= 9};
R3:={[i,j]: 1 <= i,j <= 9 && exists (alpha: j = 2alpha)};
codegen T1:R2,T2:R3;
codegen 2 T1:R2,T2:R3;