# multiplication equivalent of the summation symbol

I was curious (even though this is a very amateur question)... what would the multiplication equivalent of sigma (the summation symbol) be? $$\sum$$ I want to do a series of multiplication of terms.... instead of addition...

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Can you reduce the size of the image? –  user17762 Mar 4 '11 at 0:27
capital pi for product (like capital sigma for sum), for instance: $$\sin(\pi z)=\pi z\prod_{n=1}^{\infty}\Big(1-\frac{z^2}{n^2}\Big)$$ –  yoyo Mar 4 '11 at 3:23
what is this operation called? –  tekknolagi Mar 4 '11 at 6:13

It's a capital pi (for product): $\prod$. You can sometimes find useful symbols and guess what they mean from their $\LaTeX$ names, although I guess the most reliable way to find useful, well-known symbols is just to read a lot of math.

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There is also the table of mathematical symbols on wikipedia. –  Harry Stern Mar 3 '11 at 23:42
Ah! That's much better than what I said. –  Qiaochu Yuan Mar 3 '11 at 23:49
@tekknolagi By the way, to typeset this symbol in LaTeX, one would use the \prod command rather than the greek symbol \Pi (or \pi). This is similar to preferring \sum to \Sigma. –  Srivatsan Aug 31 '11 at 11:44