\varPiThe capital Greek letter Pi, represented as \varPi, is often used in mathematics and science to denote a product of a sequence of terms. It is analogous to the use of the capital Sigma (\Sigma) for summation, but instead of summing, it multiplies the terms.
Product of a sequence of terms from a_1 to a_n.
\varPi_{i=1}^{n} a_iProduct of terms in the form of (1 + x_k) from k=1 to m.
\varPi_{k=1}^{m} (1 + x_k)Product of squares of terms b_j from j=1 to p.
\varPi_{j=1}^{p} b_j^2