Dark Xillion

Dark Xillion is equal to \(10\underbrace{\uparrow\uparrow\cdots\uparrow\uparrow}_{10\uparrow6}(-10 \uparrow 6)\) in up-arrow notation. The term was coined by Wikia user BlankEntity.BlankEntity's Googology (Retrieved 10 June, 2022) Unfortunately, it is ill-defined as explained below.
== Issues ==
The arrow notation is originally defined for tuples of positive integers as explained in the arrow notation article, and it is naturally extended to tuples of non-negative integers. On the other hand, the expression "\(-10 \uparrow 6\)" in the definition is originally written as "-10^6" in the original source, and hence it should be solved as \(-10^6\), which is a negative integer. Therefore the expression \(10\underbrace{\uparrow\uparrow\cdots\uparrow\uparrow}_{10\uparrow6}(-10 \uparrow 6)\) is ill-formed, because it is given as the application of arrow notation to a tuple of numbers including a negative integer. Therefore it is ill-defined.
== Sources ==
Category:Numbers
Category:Numbers by BlankEntity
Category:Class 0
Category:Incomplete