@article{KARR1985303,
    Abstract = {This paper discusses some of the mathematical aspects of an algorithm for finding formulas for finite sums. The results presented here concern a property of difference fields which show that the algorithm does not divide by zero, and an analogue to Liouville's theorem on elementary integrals.},
    Author = {Karr, Michael},
    File = {Theory of Summation in Finite Terms - 1-s2.0-S0747717185800389-main - v.pdf},
    ISSN = {0747-7171},
    Journal = {Journal of Symbolic Computation},
    Number = {3},
    Pages = {303-315},
    Title = {Theory of Summation in Finite Terms},
    URL = {https://www.sciencedirect.com/science/article/pii/S0747717185800389},
    Volume = {1},
    Year = {1985},
    bdsk-url-1 = {https://www.sciencedirect.com/science/article/pii/S0747717185800389},
    bdsk-url-2 = {https://doi.org/10.1016/S0747-7171(85)80038-9},
    date-added = {2021-04-02 10:56:06 +0200},
    date-modified = {2021-04-02 10:56:06 +0200},
    doi = {10.1016/S0747-7171(85)80038-9}
}

@article{KARR1985303, Abstract = {This paper discusses some of the mathematical aspects of an algorithm for finding formulas for finite sums. The results presented here concern a property of difference fields which show that the algorithm does not divide by zero, and an analogue to Liouville's theorem on elementary integrals.}, Author = {Karr, Michael}, File = {Theory of Summation in Finite Terms - 1-s2.0-S0747717185800389-main - v.pdf}, ISSN = {0747-7171}, Journal = {Journal of Symbolic Computation}, Number = {3}, Pages = {303-315}, Title = {Theory of Summation in Finite Terms}, URL = {https://www.sciencedirect.com/science/article/pii/S0747717185800389}, Volume = {1}, Year = {1985}, bdsk-url-1 = {https://www.sciencedirect.com/science/article/pii/S0747717185800389}, bdsk-url-2 = {https://doi.org/10.1016/S0747-7171(85)80038-9}, date-added = {2021-04-02 10:56:06 +0200}, date-modified = {2021-04-02 10:56:06 +0200}, doi = {10.1016/S0747-7171(85)80038-9} }