Question: How to write summation

I want to write  in maple using summation notation for symbolic calculation. The output should come as 

 

W_1exp(k_1.q)+W_2exp(k_2.q)+W_3exp(k_3.q)

where k_j.q are the dot product of the vectors k_j and q. 

mp.mw

How to do this. Please help. The summation is not working for me, only suffix k is coming  

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