Dependence distance

In many common examples, the set of solution pairs is characterised easily:

Definition: dependence distance

• If, for all solution pairs (I₁,I₂),
  
  I₁ = I₂ - k
  
  
  then the dependence distance is k

For example in the loop we considered earlier,

We find that $S_2 ~\delta_{<}~ S_2$ with dependence distance 1.

((of course there are many cases where the difference is not constant and so the dependence cannot be summarised this way)).