Salas, Jesús, and Alan D. Sokal. “The Graham–Knuth–Patashnik Recurrence: Symmetries and Continued Fractions”. The Electronic Journal of Combinatorics 28, no. 2 (May 7, 2021): P2.18. Accessed March 29, 2026. https://www.combinatorics.org/ojs/index.php/eljc/article/view/v28i2p18.