On the Summability of Bivariate Rational Functions
نویسندگان
چکیده
We present criteria for deciding whether a bivariate rational function in two variables can be written as a sum of two (q-)differences of bivariate rational functions. Using these criteria, we show how certain double sums can be evaluated, first, in terms of single sums and, finally, in terms of values of special functions.
منابع مشابه
An Algorithm for Deciding the Summability of Bivariate Rational Functions
Let ∆xf(x, y) = f(x + 1, y) − f(x, y) and ∆yf(x, y) = f(x, y + 1) − f(x, y) be the difference operators with respect to x and y. A rational function f(x, y) is called summable if there exist rational functions g(x, y) and h(x, y) such that f(x, y) = ∆xg(x, y)+ ∆yh(x, y). Recently, Chen and Singer presented a method for deciding whether a rational function is summable. To implement their method ...
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عنوان ژورنال:
- CoRR
دوره abs/1210.6366 شماره
صفحات -
تاریخ انتشار 2012