The Neither A Subset Of Nor Equal To symbol (⊈). Copy and paste it, or use its Unicode, HTML, and CSS codes.
More from Math.
The quickest way is to copy ⊈ from this page and paste it anywhere. You can also insert it with its Unicode, HTML, or alt code listed above.
⊈ is U+2288 (decimal 8840).
Use ⊈ in HTML to render ⊈ on a web page.
On Windows you can type it with Alt+8840 (hold Alt and enter the number on the numeric keypad).
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