A SYMMETRICAL q - EULERIAN IDENTITY
نویسنده
چکیده
We find a q-analog of the following symmetrical identity involving binomial coefficients ( n m ) and Eulerian numbers An,m, due to Chung, Graham and Knuth [J. Comb., 1 (2010), 29–38]: ∑ k≥0 ( a + b k ) Ak,a−1 = ∑ k≥0 ( a + b k ) Ak,b−1. We give two proofs, using generating function and bijections, respectively.
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