I What does product part of Laughlin wave function mean?

George Keeling
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confused by product symbol with two subscripts
I am looking at the Laughlin wave function and it contains the term
$$\prod_{j<k}^{N}\left(z_j-z_k\right)^q$$
In Wikipedia the lower index on ##\Pi## is ##1\le i<j\le N## and there is no upper index. I'm not sure what either mean. For example would
$$\prod_{j<k}^{N}\left(z_j-z_k\right)^q=\prod_{k=2}^{N}\left[\prod_{j=1}^{k-1}\left(z_j-z_k\right)^q\right]?$$
(It seems that ##k## cannot be 1 because there would be nothing to multiply in the second product). I'm not sure what else the expression could mean.

For ##N=3## that would give ##\ \left(z_1-z_2\right)^q\left(z_1-z_3\right)^q\left(z_2-z_3\right)^q## I think.
 
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Yes, this is the meaning of that product symbol with two subscripts.
 
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I am looking at the Laughlin wave function and it contains the term $$\prod_{j<k}^{N}\left(z_j-z_k\right)^q$$ In Wikipedia the lower index on ##\Pi## is ##1\le i<j\le N## and there is no upper index. I'm not sure what either mean. For example would $$\prod_{j<k}^{N}\left(z_j-z_k\right)^q=\prod_{k=2}^{N}\left[\prod_{j=1}^{k-1}\left(z_j-z_k\right)^q\right]?$$ (It seems that ##k## cannot be 1 because there would be nothing to multiply in the second product). I'm not sure what else the...
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