Finite arrangement of infinite sums or products

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Infinite sum and product changes value under (infinite) arrangement of the terms, if the sum or product exists. I was wondering what happens if I only swap a finite number of terms in the sum / product. My guess is that the value shouldn't change in this case.

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An absolutely convergent infinite sum will not change value under rearrangement. A conditionally convergent sum that is not absolutely convergent can be made to sum to any number by the Riemann rearrangement theorem. For products you can just take the logs and use the sum theorems.

Yes, if you change the order of a finite number of terms it will not matter. There is a last term changed. The sum or product out to there will be the same by commutativity and associativity, then the rest is the same.