Changed the notation in the example that confused me: added “+” superscripts to the (pre)set symbols.
]]>That’s a weird convention, probably best to change it no?
]]>Oh wait. False alarm. That text is using for positive integers only.
]]>The example of as a Bishop set on the preset is wrong. You need to rule out zero denominators. The definition currently on the page is not a Bishop set at all, because makes the relation intransitive.
I’m not sure how it should be changed to illustrate the point that the same preset can get distinct sets. Maybe a different example entirely?
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