Modeling the equation with lots of sums

GAMS
1

hi, do anyone knows how to code this in games? a little example would be fine :slight_smile:
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2

hello, this is an example. You must define the necessary variables and sets
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in GAMS:
sum((i,j,q,p),X(i,j,q,p)*C1(i,j,q,p))

best