Hi, thanks for the answer. I am trying algebraic approach to the NP-hard problem independent set in graph. For integer n, working over QQ['x',n] (probably another base field will work too). I have the following constraints: 1. x[i]*(x[i]-1)=0, i <=0 <n 2. For a set of integer pairs (u_i,v_i) add the constraints x[u_i]*x[v_i]=0
So far groebner basis are easy to compute. The additional hard constraint is 3. sum(x_i)=k for integer k. Are there special cases (u_i,v_i),k and base field for solving (1),(2),(3)? Experimentally groebner basis work, but adding (3) makes the computation slow. -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/sage-devel/CAGUWgD9sQSSWiGnEmQtYnHxO1FwW_VxCaddGaj01eMi0eDZEeg%40mail.gmail.com.
