Here's an alternative for you to consider:

    mySum[p_List, iMin_] :=
     Row[{#, Times @@@ #}, "\[LongEqual]"] &[
       Tr @ MapIndexed[CenterDot[iMin - 1 + #2[[1]], #] &, 1/7 {3, 2, 0, 2}]
     ]
    
    mySum[1/7 {3, 2, 0, 2}, 0]

![enter image description here][1]


  [1]: https://i.sstatic.net/ayzPt.png