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arXiv · 2504.00006

Self-graphing equations

Samuel Allen Alexander
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Abstract

Can you find an xy-equation that, when graphed, writes itself on the plane? This idea became internet-famous when a Wikipedia article on Tupper's self-referential formula went viral in 2012. Under scrutiny, the question has two flaws: it is meaningless (it depends on typography) and it is trivial (for reasons we will explain). We fix these flaws by formalizing the problem, and we give a very general solution using techniques from computability theory.

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Samuel Allen Alexander. 2025-03-18. Self-graphing equations. https://arxiv.org/abs/2504.00006

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