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I have two sets of items. Every item has a score. I'm finding the sum of the scores of the items of the intersection of both sets.

What would the best way to notate this be?

An example:

A = {a, b, c, d}
B = {c, d, e}
The scores are:
a -> 9
b -> 8
c -> 7
d -> 6
e -> 5
The result is the sum of the values of c and d, 7 + 6 = 13
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up vote 1 down vote accepted

For arbitrary sets $A$ and $B$, where the score of an element $a$ is $s(a)$, denote the sum of the scores of the elements in their intersection $\sum_{a\in A \cap B} s(a)$.

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