Sigma Notation: Definition and Examples

[bitttttor]

What does this mean? (see attachment)

"Where b is a block defined by the contiguity condition c that may exist between elements of s, and n is the number of elements in that block"

I know is not possible to get a solution without the actual function, but how does this reads?

 

[HallsofIvy]

That notation is a little ambiguous. Just
$$\sum_{c\in S} f(c)$$
would mean "caclulate f(c) for all c contained in set S, then add". But the "n" is problematic- the set S, in general, doesn't even have to be a set of numbers.

My best guest would be "calculate f(c) for all c contained in set S, that are less than or equal to n, then add them."

 

[bitttttor]

Great, thank you.

 

[NascentOxygen]

bitttttor, are you able to say more about the background to this? In what context did you find it?