NotSubset 
NotSubset[x,y,…]
displays as .
Details
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- NotSubset[x,y,…] has no built-in meaning.
is by default interpreted as NotSubset[x,y].
can be entered as \[NotSubset] or
!sub
.
Examples
Basic Examples (1)
Wolfram Research (1996), NotSubset, Wolfram Language function, https://reference.wolfram.com/language/ref/NotSubset.html.
Text
Wolfram Research (1996), NotSubset, Wolfram Language function, https://reference.wolfram.com/language/ref/NotSubset.html.
CMS
Wolfram Language. 1996. "NotSubset." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/NotSubset.html.
APA
Wolfram Language. (1996). NotSubset. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/NotSubset.html