Proposed problems should be submitted online at americanmathematicalmonthly.submittable.com/submit.

Proposed solutions to the problems below should be submitted by April 30, 2021, via the same link. More detailed instructions are available online. Proposed problems must not be under consideration concurrently at any other journal nor be posted to the internet before the deadline date for solutions. An asterisk (*) after the number of a problem or a part of a problem indicates that no solution is currently available.

中文翻译：

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问题与解决方案

提出的问题应在线上americanmathematicalmonthly.submittable.com/submit提交。

针对以下问题的建议解决方案应在2021年4月30日之前通过同一链接提交。可在网上找到更详细的说明。提出的问题不得在任何其他期刊上同时考虑，也不得在解决方案的截止日期之前发布到互联网上。问题编号或部分问题编号后的星号（*）表示当前没有可用的解决方案。