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Purpose: To provide a GAMS formulation for the collection
of Gupta Problems

Reference: Branch and bound experiments in convex nonlinear
integer programming, Management Science, 1533-1546, 31, 1985.

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Variables  i1,i2,objvar;

Integer Variables i1,i2;

Equations  e1;


e1..  - 0.1*(sqr(i1) + (1 + sqr(i2))/sqr(i1) + (100 + sqr(i1)*sqr(i2))/POWER(i1
     *i2,4)) + objvar =E= 1.2;

* set non default bounds

i1.lo = 1; i1.up = 200; 
i2.lo = 1; i2.up = 200; 

* set non default levels


* set non default marginals


Model m / all /;

m.limrow=0; m.limcol=0;

$if NOT '%gams.u1%' == '' $include '%gams.u1%'

Solve m using MINLP minimizing objvar;