Math Operator 15

Unicode
U+220E
Category
Math
HTML Entity
∎
CSS
\220E
The ∎ symbol, officially known as the "End of Proof" or "Tombstone" mark, is used in mathematics to visually indicate the conclusion of a formal proof. Popularized by mathematician Paul Halmos, it serves as a modern, space-saving replacement for the traditional "Q.E.D." abbreviation. While it reigns supreme in academic papers and textbooks, you might also spot it used creatively as a heavy, solid bullet point in distinct digital typography.

How to Type

Windows
Alt+8718
macOS
Control+Command+Space, then search "End of Proof"
Linux
Ctrl+Shift+U then 220E
HTML
&qed; or ∎

In Programming

In LaTeX typesetting and mathematical formatting, this symbol is generated using the \qedsymbol command (often via the amsthm package) to neatly close out proof environments.

Tags

Halmos tombstone meaning QED alternative black square math end of proof halmos mathematical black square mathematics proof complete symbol proof done symbol qed quod erat demonstrandum solid square Unicode tombstone

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