The Apl Functional Symbol Quad Diamond symbol (⌺). Copy and paste it, or use its Unicode, HTML, and CSS codes.
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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+233A (decimal 9018).
Use ⌺ in HTML to render ⌺ on a web page.
On Windows you can type it with Alt+9018 (hold Alt and enter the number on the numeric keypad).
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