主题
问题是指一个需要求出解的练习。“数学问题”的范围可以从简单的谜题到考试和竞赛问题，再到需要深刻分析才能证明的主张。
虽然并非绝对标准，但希腊人区分了“问题”（大致是指各种图形的构造）和“定理”（确立所述图形的性质；Heath 1956，第 252、262 和 264 页）。
数学中存在许多未解决的问题。最近已解决的两个著名问题包括费马最后定理（由安德鲁·怀尔斯证明）和开普勒猜想（由 T. C. 海尔斯证明）。在最突出的未解决问题中，有哥德巴赫猜想、黎曼猜想、关于存在无限多孪生素数的猜想，以及更多。K.S. 布朗、D. 爱泼斯坦、S. 芬奇和 C. 金伯林维护了大量数学未解决问题的页面。
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