The Double-Struck Small Pi symbol (ℼ). Copy and paste it, or use its Unicode, HTML, and CSS codes.
More from Letterlike Symbols.
The quickest way is to copy ℼ from this page and paste it anywhere. You can also insert it with its Unicode, HTML, or alt code listed above.
ℼ is U+213C (decimal 8508).
Use ℼ in HTML to render ℼ on a web page.
On Windows you can type it with Alt+8508 (hold Alt and enter the number on the numeric keypad).
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