* hs64.mod      OOR2-MN-3-4
* Original AMPL coding by Elena Bobrovnikova (summer 1996 at Bell Labs).

* Ref.: W. Hock and K. Schittkowski, Test Examples for Nonlinear Programming
* Codes.  Lecture Notes in Economics and Mathematical Systems, v. 187,
* Springer-Verlag, New York, 1981, p. 86.

* Number of variables: 3
* Number of constraints: 4
* Objective separable
* Objective nonconvex
* Nonlinear constraints

Set I /1*3/;

Variable x[I],
         Obj ;
Equation Constr ,
         Defobj ;

Defobj.. Obj =e=
         5 * x['1'] +  50000 / x['1'] + 20 * x['2'] + 72000 / x['2'] + 10 *
             x['3'] + 144000 / x['3'];
Constr..   1 =g= 4/x['1'] + 32/x['2'] + 120/x['3'];

x.lo[I]=1E-5 ;
x.l[I]=1     ;

model hs64 /all/;
solve hs64 using nlp minimize Obj;

display Obj.l;
display x.l;