Mathematical problem

Happy Ending problem Hilbert's sixth problem Josephus problem social golfer problem Hilbert's twelfth problem Hilbert's ninth problem Hilbert's eighth problem Hilbert's eighteenth problem differential equation hexagonal tortoise problem coupon collector's problem Closest pair of points problem related rates Mathematical problems of the classical antiquity Cutting stock problem boundary value problem Hilbert's second problem kissing number problem secretary problem The Weber Problem well-posed problem Three Prisoners problem inverse problem Moser's worm problem Hilbert's 24th problem logic puzzle two envelopes problem Einstein problem equation solving Hilbert space transportation theory squaring the circle integrable system Plateau's problem Monty Hall problem art gallery problem Archimedes' cattle problem Riemann hypothesis wheat and chessboard problem Gauss circle problem doubling the cube inscribed square problem Landau's problems coin problem class number problem Hilbert's seventeenth problem Stability of the Solar System Hilbert's sixteenth problem Turán's brick factory problem Boolean Pythagorean triples problem