Hi, how do I interpret the last sum:(adsbygoogle = window.adsbygoogle || []).push({});

http://planetmath.org/encyclopedia/LagrangesIdentity.html [Broken]

Sum (...)

1<=k < j <= n

Is it the double sum:

Sum( Sum( (a_k*b_j - a_j*b_k)^2 from k = 1 to n) from j = 2 to n ) ?

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# Homework Help: Lagrange Identity Sum Notation

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