Monthly Archives: July 2020

Rational dodecahedron inscribed in unit sphere

Moritz Firsching asked in 2016 whether there exists a dodecahedron, combinatorially equivalent to a regular dodecahedron, with rational vertices lying on the unit sphere. The difficulty arises from the combination of three constraints: The twelve pentagonal faces must all be … Continue reading

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Fast-growing functions revisited

There have been many exciting results proved by members of the Googology wiki, a website concerned with fast-growing functions. Some of the highlights include: Wythagoras’s construction of an 18-state Turing machine which takes more than Graham’s number of steps to … Continue reading

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