symbolic n,m;
incomingKnown := { [i1,i2] : exists ( alpha : i1+3alpha = 1+i2 ) && 
                   i1 = n && i2 = m};


codegen incomingKnown;
incomingKnown := { [i1,i2] : exists ( alpha : i1+2alpha = 1+i2 ) &&
                   i1 = n && i2 = m};


codegen incomingKnown;