I've been clawing at my mind for a while regarding this, I pray somebody can help me.(adsbygoogle = window.adsbygoogle || []).push({});

I was implementing a method from a computer science paper when I came accross this:

[PLAIN]http://www.mattkent.eu/challenge.png [Broken]

Bearing in mind thatxis a vector, epsilon is a vector of integers (andxraised to this is performed component wise), I can't tell what exactly the Sigma is summing.

Firstly what does a sigma of indeximean in the matrix A? What exactly would be summed there? Is it the 'sum of the vector components for a given i' or the 'sum of all vectors where each has been raised to epsilon'?

And secondly, in the definition of thebvector, what is the sigma doing here? There's absolutely no index or limit associated with it. Thetvalue is essentially a constant. So is this saying 'sum up the vectors components (once multiplied witht)' ?

I'm at a loss. Please help super mathematicians.

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# Specific Sigma Notation

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