# Meaning of a mathematical symbol?

1. Feb 22, 2008

### uart

Ok first a warning, this may be completely bogus as it was a symbol (or actually a notation) that I didn't recognize in a blackboard full of equations from a stupid "teen" movie. It may have been completely meaningless.

I was visiting a friend today and her daughter was playing a DVD of some dumb kids/teen movie. One thing caught my eye when they showed the "geeks" working at a blackboard full of infinite sum type identities. Curiosity got the better of me and I got here to pause it to so I could take a look and see if they were real identities or just gibberish (as equations in the background on blackboards in movies sometimes are).

Well I wasn't able to tell if they were gibberish or not because there was one bit of notation in all the equations that I'm not familiar with. As part of an infinite sum over "n" it had terms like,

$$\left( \frac{1}{2} \right)^3_n$$.

Does anyone recognize that or is it just nonsense?

2. Feb 22, 2008

### CRGreathouse

$$\left( \frac{1}{2} \right)^3$$ could be a Legendre/Jacobi/Kronecker symbol, raised to the third power... but there's no reason for it to be cubed if there's just a 1 in the upper part, so combined with the subscript which I can't figure out, it's probably nothing.

Of course if not for the subscript it could also be (1/2)^3 = 1/8, but there's be no reason to do that in a loop.

3. Feb 23, 2008

### uart

Thanks for the reply. Ok then it looks like the equations were just nonsense. They definitely looked like nonsense but I couldn't be sure since I didn't recognize that part of the notation. If I get a chance to see this DVD again I'll write down one of the "identies" in full and post it here for a laugh.

4. Feb 23, 2008

### CRGreathouse

Yeah, I'd like to see them. If they end up being real equations that I just didn't recognize we can have a laugh about that too. :uhh: