> The article shows this graphically, but there is no formal proof (although the Adler & Tanton paper is mentioned).

Well, if that interested you, you could have downloaded the paper and read it. To me your comment sounds a shade entitled, as if the blog author is under an obligation to do all the work. Sometimes one has to do the work themselves.

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whyandgrowth a day ago | parent [-]

If the author had provided links to explanations or additional materials for those who want to understand the formal reasoning more deeply.

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dpassens a day ago | parent [-]

And why does the linked paper not qualify as such a link?

	▲	whyandgrowth a day ago \| parent \| next [-]
		P.S. Sorry, I was wrong.
	▲	whyandgrowth a day ago \| parent \| prev [-]
		Good point. I just thought that a direct link or summary of the formal reasoning would have made it easier for readers unfamiliar with the topic. But fair enough, the linked paper does cover it.