Textbook examples of recursion
<|reference_start|>Textbook examples of recursion: We discuss properties of recursive schemas related to McCarthy's ``91 function'' and to Takeuchi's triple recursion. Several theorems are proposed as interesting candidates for machine verification, and some intriguing open questions are raised.<|reference_end|>
@article{knuth1991textbook,
    title={Textbook examples of recursion},
    author={Donald E. Knuth},
    journal={Artificial intelligence and mathematical theory of computation},
    year={1991},
    number={Knuth migration 11/2004 207-229, Academic Press, Boston, MA, 1991},
    archivePrefix={arXiv},
    eprint={cs/9301113},
    primaryClass={cs.CC}
}