Consider objects like
obj= (Sum[Subscript[A, i], {i, 1, 5}] Sum[Subscript[A, i], {i, 3, 6}] Sum[Subscript[A, i], {i, 2, 3}])/(
Sum[Subscript[A, i], {i, 3, 8}] Sum[Subscript[A, i], {i, 1, 2}] Sum[Subscript[A, i], {i, 4, 6}])
I would like to have a substitution rule myRule
that would perform the following replacement
obj /. myRule
for sequences of sums of $A_i$ of any lengths, and with indices not necessarily consecutive and not necessarily integer. How can this be done?