By means of the recursive construction method, we examine a class of multiple sums (with a free variable "$ x $") for circular products of binomial coefficients. They are first expressed as coefficients of bivariate rational functions. Then the rational generating functions are determined by deftly employing Knuth's bracket calculus, resultants of polynomials, and Hadamard products of rational functions.
Citation: Marta Na Chen, Wenchang Chu. Generating functions for circular sums of binomial products[J]. AIMS Mathematics, 2025, 10(12): 28182-28206. doi: 10.3934/math.20251239
By means of the recursive construction method, we examine a class of multiple sums (with a free variable "$ x $") for circular products of binomial coefficients. They are first expressed as coefficients of bivariate rational functions. Then the rational generating functions are determined by deftly employing Knuth's bracket calculus, resultants of polynomials, and Hadamard products of rational functions.
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