Sigma notation can be difficult to read if you're not used to it. It's actually quite straightforward, but for some reason large Greek letters can stun the brain for several seconds. (This happens to me often and is probably a sign of poor nutrition or a brain injury resulting from sitting too close to the television as a kid.)

Sigma notation can be difficult to read if you're not used to it. It's actually quite straightforward, but for some reason large Greek letters can stun the brain for several seconds. (This happens to me often and is probably a sign of poor nutrition.)

Sigma notation can be difficult to read if you're not used to it.